A subsidiary book is a type of book used in accounting to record specific types of transactions. Out of the options given, only the cash book is a subsidiary book as it is used to record cash transactions. Bank statement is a record of the transactions that occur in the bank account of a company. Control accounts are used to summarize and monitor the transactions of a particular ledger account, whereas trial balance is a statement that shows the balances of all ledger accounts in a double-entry accounting system.