Correction of errors

Good Day John
I have a question:

The bookkeeper of Peri made the following mistakes
Sales returns of $384 were credited to the purchases returns account
Purchases returns of $296 were debited to the sales returns account
Which one of the following journal entries will correct the errors?
The correct answer is:

Dr Sales returns 88
Dr Purchase returns 88
Cr suspense account 176

Could you please explain why this is the case, sir?
Thank you a lot