Answer:
The function of the infinitive phrase is:
B. object.
Step-by-step explanation:
Infinitive phrases are comprised of a verb in the infinitive form (to + base form of the verb) and modifiers or other words related to the infinitive. They can function as adjectives, adverbs, or nouns in a sentence.
In the sentence "The gymnast loved to compete," the infinitive phrase is "to compete." In this case it functions as a noun, more specifically as the object of the verb "loved", meaning it is the "thing" being acted upon. The gymnast loves what? To compete.