Concept:A contra entry is a transaction recorded on both the debit and credit sides of the cash book to offset the same amount.Explanation:When cash is withdrawn for office use or cash is deposited into the bank, the cash book is affected on both sides.One side records the increase in one account, while the other side records the decrease in another account.Because both entries are for the same amount and appear together in the cash book, they cancel or offset each other.This type of double entry is specifically called a contra entry.Answer:B. contra entry