After the pronoun "whose" we don't use an article, so alternative b) is correct: This is the lady whose daughter is a youtuber.
As for the remaining alternatives:
a) I have already studied for both tests.
Between the numeral "both" and a noun, we use the article (the word "tests" is a noun).
But, in these cases, for example, we don't use an article after "both": I had a good grade in both. or Both took the test.
c) Florianópolis is famous for its beaches.
Generally, we don't use article before place names. However, if the name of the place is accompanied by a quality, we use an article, as in the following alternative, in which the word "enchantadora" qualifies Florianópolis.
d) The charming Florianópolis is famous for its beaches.
Indicate the alternative in which we can use the masculine article with all the words.
a) lettuce, mascot, graffiti
b) spouse, pity, champagne
c) mascot, graffiti, champagne
d) radio, spouse, graffiti
e) spouse, double, graffiti
The words spouse, pity and champagne are masculine nouns: the spouse, the pity, the champagne.
As for the remaining alternatives:
a) lettuce, mascot, graffiti
All of them are feminine nouns: the lettuce, the mascot, the graffiti
c) mascot, graffiti, champagne
The words mascot and graffiti are feminine nouns: the mascot, the graffiti. The word champagne is a masculine noun: champagne.
d) radio, spouse, graffiti
The word radio is a masculine noun when referring to the device (the radio) and a feminine noun when referring to the station (the radio).
The word spouse is a masculine noun (the spouse) and the word graffiti is a feminine noun (the graffiti).
e) spouse, double, graffiti
The word look-alike is a masculine noun when referring to the masculine gender (the look-alike) and a feminine noun when referring to the feminine gender (the look-alike).
The word spouse is a masculine noun (the spouse) and the word graffiti is a feminine noun (the graffiti).
Indicate the alternative in which the article was used to noun a word.
In this case, the word "why" means reason: I understand why you're upset.
When we use an article before a word that is not a noun, it takes on the value of a noun. For example, the word "no" is an adverb (I didn't hear.), but in this sentence, it has noun value: I heard a no.
As for the remaining alternatives:
a) I don't know how to raise the morale of this team. (the definite article "the" is accompanying the masculine noun "moral")
b) This is the book you need. (the definite article "the" is indicating or defining the book)
d) The daughter is the spitting image of her mother. and e) The son is the face of the father. (the definite articles "a" are indicating or defining someone's face)
a) this is The 6th grade Portuguese teacher.
The definite article "a" is specifically indicating who the 6th grade Portuguese teacher is.
b) found to the my friends mothers yesterday.
The definite article "as" is specifically indicating who the mothers I encountered are.
c) Today, I met one lady at the supermarket.
The indefinite article "one" is indicating that I met one lady among many ladies (any lady) and not one lady specifically.
d) we received some visits from afar.
The indefinite article "ones" is vaguely indicating that we received visits, that is, it does not indicate that we received a specific visit, for example: We received the visit we expected.
and you have O book that the teacher indicated?
The definite article "the" is indicating, in a specific way, what book it is about, that is, the one that was indicated by the teacher.
f) I bought more some sweets for the party.
The indefinite article "ones" is vaguely indicating that I bought candy, but without specifying which candy I bought.
g) By chance, one gentleman with mustache and hat stopped by?
The indefinite article "one" conveys the idea of a gentleman, among many, who possibly presents some characteristics.
H) You books you ordered have not yet arrived.
The definite article "the" is specifically indicating what book it is about, that is, the one you ordered.
Indicate the alternative in which the article was used to qualify the noun.
The prayer "This is the game." conveys the idea that that game stands out among the others, that is, among many, that is "the" game, not just any game.
As for the remaining alternatives:
a) This is one of the games I told you about. (the indefinite article "one" conveys that there are multiple games and this is just one of them)
c) What is your favorite game? (the definite article "the" indicates that there is one game in particular that is my favorite)
d) The boy forgot two notebooks on the bus. (the definite article "the" indicates who forgot the notebook, a particular boy and not just any boy)
e) The boy found the notebooks he had lost. (the definite article "the" indicates who forgot the notebook and the definite article "the" specifically indicates which notebooks were, i.e. the ones the boy had lost)
Correction: I used the grams of flour you told me to use.
The word gram is a masculine noun when referring to weight (gram) and a feminine noun when referring to vegetation (grass). Therefore, they are correct:
d) This scale does not weigh grams accurately. (Weight)
e) The grass in the stadium was recently changed. (vegetation)
The noun head is masculine when it has the sense of leader, as in alternative b) Do you have a head on the team?
But, it is feminine when referring to the body, as in alternative c) What do you have on your mind?
The first sentence is indicating the total time someone studied, i.e. four to five hours.
The second prayer is indicating the exact time someone was studying, that is, it started at four o'clock and ended at five.
FERNANDES, Marcia. Exercises on articles (with explained answers).All Matter, [n.d.]. Available in: https://www.todamateria.com.br/exercicios-sobre-artigos/. Access at: