The correct answer is A. accumulator.
An accumulator is a register that stores the result of an arithmetic or logical operation. It is used in both the ALU and the control section of a computer.
A register is a temporary storage location for data. It is used to store data that is being processed by the CPU.
An adder is a circuit that performs addition. It is used to add two numbers together.
A decoder is a circuit that converts a code into a set of signals. It is used to decode instructions from the control unit.
E is not the correct answer because it is not a storage location.