Answer:
C) "Oh no," he grumbled impatiently under his breath, "Now I have to start all over."
Explanation:
There are several instances where using a comma brings clarity and cohesiveness to your text. For example, a comma should be used when joining two independent clauses with a conjunction:
We could not make it in time, so we did not go.
A comma is also useful after an introductory phrase:
Forced to eat on her own, she decided to at least watch TV.
Commas should also be used when introducing direct quotes, such as in this example.
