Which sentence would best support the claim that, in order to be healthier, teenagers should avoid sodas and snacks made with sugar?
a. studies show that high-sugar snacks can cause fatigue and increase hunger.
b. buying fruit in bulk can make it as inexpensive as sugary snacks.
c. many parents do not allow their children to eat sugar-filled snacks and sodas.
d. some teenagers cannot eat sugary snacks because of allergies and diabetes.

A. Studies show that high-sugar snacks can cause fatigue and increase hunger.

Explanation:

This sentence is the only one that in a logical and coherent way supports the claim. As the claim refers to teenagers' health related to sugar in snacks, the supporting sentence must give an example of a health problem caused by sugar consumption. We can see that it succesfully does it by showing that high-sugar snacks cause fatigue and more hunger. It addreses the two variables found in the claim. It also appeals to science to make it's point, this is empirical evidence that the reader can compare or find in a research done by an expert. This gives legitimacy to the argument.

themselves

an intensive pronoun is a pronoun that ends in self or selves, such as himself, herself, themselves, yourself, ourselves. since band members is a third person plural, the correct intensive pronoun would be themselves. if the band was talked about as a collective noun, itself would be the appropriate intensive pronoun. intensive pronouns are used to add emphasis to the noun it's modifying which is why it directly follows it.