Answer:
You didn't mention what the question is about, but I'm going to guess it's not D or B. So it's either A or C.
A. says something like when someone is sleep deprived, they are so tired and out of it that they might confess to committing the crime. C. says something like when the suspect is sleep deprived, they are unable to understand what they are saying, therefore they could confess to a crime they didn't commit.
I'll take an educated guess and say it's
C. Sleep deprivation can cause distress in the body and mind, which makes suspects unable to understand what they are saying or the consequences of their confession.
Yes, commas are used for clauses that help to provide a fuller picture, even when not necessary. Dashes can be used for a similar purpose as they are used here, but i don't believe it's appropriate in this sentence. Parentheses can only be used for information that can be completely written off without having any effect on the sentence.
