A register in which of the following that holds the current instruction while it is being executed is called instruction register.
A register in the CPU holds the current instruction while it is being executed is called instruction register.
In computing, an instruction register (IR) is the part of a CPU's control unit that holds the instruction currently being executed or decoded. ... In the instruction cycle, the instruction is loaded into the instruction register after the processor fetches it from the memory location pointed to by the program counter.
A processor register (CPU register) is one of a small set of data holding places that are part of the computer processor. A register may hold an instruction, a storage address, or any kind of data (such as a bit sequence or individual characters). Some instructions specify registers as part of the instruction.