Time, like water, seems to sit in a pot unable to boil if your eye isn't constantly on it. What is effect of the simile used in this sentence?

Ato show that a watch is not necessary to tell time

Bto show that the author is not prepared for cooking morning meals

Cto show that if one is not focused on time, it seems to move slowly

Dto show that if one is not focused on time, it will speed away quickly