The three activities in the list all need to have a parallel structure, and be grammatically correct, ruling out the answer choice featuring the construction "to running . . ." The best answer choice, therefore, is "to swim, to hike, and to run on the camp's property."

Any list like the one underlined in the sentence must feature a parallel structure in word form. Otherwise, as in the sentence, it compares unlike things such as a "want to fight" and "discussing important topics." The sentence needs to be improved to feature a parallel structure, something only done by the answer choice "to fight, to sing, and to discuss important topics."

The list that forms the underlined portion of the sentence has three items, but one is in a different format to the others, meaning unlike things are grouped together. Any such list needs to feature a parallel structure, where all the forms match each other. The only answer choice that appropriately does this is "for wearing makeup, having parties, and dressing inappropriately."

The list underlined in the sentence contains three unlike things, as the forms of the words are all quite different. All such lists need to feature a parallel structure to show it is a list of similar things. The correct answer choice, therefore, is "Fishing, hunting, and foraging." 

The two elements in the underlined portion of the sentence describe two different kinds of action, "reading" and "to watch." They need to be changed to have a similar structure to be described in the same clause; therefore, the correct answer choice is "reading too little and watching too much TV."

Logically, the rejection of art would be disturbing to pundits (a noun defined as learned individuals) and laymen. Using this knowledge, students could eliminate any answer choice that would say that this would not be disturbing. Even without this knowledge, based on the rule of concordance, students would know that the only plausible options are "both pundits and laymen" or "neither pundits nor laymen," because "neither" always goes with "nor" and "either" always goes with "or." So, the correct answer is "both pundits and laymen."

The verb structure in a sentence involving parallel structure, such as this one, should remain constant. In the original sentence, there are two progressive verbs followed by a noun that would be better written as a verb. Changing "design of clothing" to "designing clothing" results in a more consistent parallel structure that involves three progressive verbs.

This sentence uses parallel structure, so we need to make sure both of its verbs match in terms of tense and verb form. We cannot change "to play tennis," so we need to make "riding his bicycle" match the tense and verb form of "to play tennis." "To play" is an infinitive, so we need to change "riding" to "to ride," another infinitive, yielding "to ride his bicycle," the correct answer.

The list that is underlined in the sentence has an issue with containing unlike forms. Therefore, they should be changed to have a consistent parallel structure. "Singing, dancing, and acting" is the only answer choice that uses the appropriate structure.

The list featured in the underlined section is united by the same verb, but it does not have the same structure in all of its elements, two of which are gerunds ("kicking" and "running") and one of which is a noun phrase ("defensive skills"). The sentence needs to have its elements changed so that they match each other. Only "at kicking, running, and defending" features the appropriate parallel structure.