The correct answer is B. Buffer.
A buffer is a temporary storage area used to compensate for the difference in speed at which the different units can handle data. It is used to store data that is being transferred from one device to another, or from one process to another. This allows the devices or processes to operate at their own speeds without having to wait for the other to finish.
Memory is a general term for any device that can store data. It can be used to store both temporary and permanent data. Temporary data is data that is only needed for a short period of time, such as the data that is being used by a program that is currently running. Permanent data is data that is stored for a long period of time, such as the data that is stored on a hard drive.
An accumulator is a register that is used to store the result of a calculation. It is typically used in arithmetic and logic units (ALUs) to store the intermediate results of a calculation.
An address is a unique identifier that is used to locate a specific location in memory. It is typically used by the CPU to access data that is stored in memory.