Identify the use of the infinitive phrase in the following sentence.

to finish a marathon is elizabeth's goal for the year.

a) noun
b) adjective
c) adverb

What is the best way to improve the conclusion? add a sentence to the ending that summarizes the writer’s topic. add a sentence to the middle that reflects on the writer’s experiences. revise the final sentence to have a different tone. revise the first sentence to state a future goal.