Answer:C)
Peter is exercising because he wants to be on the lacrosse team.
Explanation:
A gerund is formed <em>when we add -ing to a verb</em>. It functions as a noun in a sentence, while gerund/gerund phrase can be a subject or an object (direct/indirect) of a sentence. For example, gerund form of the verb<em> 'to read'</em> is <em>reading. </em>
However, gerund should not be confused with continuous tenses. In sentence - <em>Peter is exercising because he wants to be on the lacrosse team</em>, <em>is exercising</em> is not a gerund, but is a verb form, present continuous tense of verb<em> to exercise</em> (verb to be + ing form).
