Answer:
C. Simile
Step-by-step explanation:
The correct answer is simile.
Simile is a figure of speech that uses "as" and "like" to compare two things. It is used in comparing one thing with another thing that is of a different kind.
This tries to compare "when friends can't be found" to "a bridge over troubled water". Simile differs from metaphor because it compares two things directly by highlighting the similarities between those two things using "like" or "as". Metaphors actually create an implicit comparison.