Which of the following contains an example of an infinitive?

B). To run is to feel alive.

Explanation:

Infinitives are illustrated as the basic form of the verb that connects it to a specific subject without any articulation. These are the non-finite verbs that usually begin with 'to' and function as nouns, adjectives, or adverbs. As per the questions, the option that employs an infinitive in it is option B as it includes the infinitives twice 'to run' and 'to feel' as they exemplify the simple forms of the verbs. Thus, option B is the correct answer.

this is a good question! i'll do some research and come back when i have the answer!