Which of the following is an example of a contraction?

A contraction is a shortened form of a word or group of words that omits certain letters or sounds. In the given example of "can't," the contraction combines the words "can" and "not," where the letter "o" is omitted. This shortening provides a more efficient way to convey the negative form of the verb "can." It is a common feature in English that makes speech and writing more fluid and natural.

In contrast, the other options listed consist of full phrases or combinations of pronouns and verbs without any omitted letters. "She is" and "We are" show complete forms of the verb "to be," while "They will" represents a future tense construction without any contraction present. Thus, “can’t” is the only option that exemplifies what a contraction is, demonstrating the blending of two words into one distinct form.