The instruction "MOV C, A" is an assembly language command used in microcontrollers and processors, particularly in the Intel 8085 architecture. This command copies the contents of the accumulator register, denoted as A, into the register C. The accumulator is a special register used for arithmetic and logic operations, while register C is one of the general-purpose registers. This operation is essential for data manipulation, allowing the programmer to transfer data between registers efficiently. After executing "MOV C, A," the value in register C will be the same as that in the accumulator, enabling further processing or calculations without altering the original data in A.