Which is the best use of punctuation?

C: Upon hearing her diagnosis, she was filled with one emotion: relief.

Explanation:

edg2020

what is the context here? we need to know what story you're talking about : )

there is a sequence and logical steps to give an answer of a trouble.

1) strategy is necessary to develop an project idea.

2) to study and know the environment where you are going to work ( ecosystem).

3)   the materials resources to built the ideas.

4) to give a priority order in the context that you study. in this case human needs.