Answer: decode unit
Explanation: The decode unit is responsible to for fetching instructions then break them down or translate those instructions into sequence which can be understood by the control unit. Decoding is usually carried out by control unit of the central processing unit. Instructions is usually split into two parts, The operation code which is the command to be carried out or executed by the computer and the operand which is where data will be read from or written to, and the number of operands required to perform an operation.