Which sentence contains an infinitive or infinitive phrase? A. Can I take your car to the movies? B. Grocery shopping took forever this morning. C. The letters to send are in the folder. D. The squirrel is running up the tree away from the dog.

Correct answer is:

C. The letters to send are in the folder.

An infinitive phrase contains the word "To" followed by a verb. So the word "To" in the sentence is followed by the verb send

An infinitive phrase is a phrase that proceeds after the noun or subject and the modifier. This kind of phrase begins with the word "to" plus the modifier. In this case, among the sentences given, the one that has "to" only is sentence A where the modifier is the movies