Instruction format of machine level language consists of OPCODE and _______ .

Question

Accepted Answer

The correct option is (2):
The instruction format of a machine-level language instruction is fundamentally divided into two major components: the Operation Code (OPCODE) and the Operand field(s). The OPCODE is a fixed-length collection of bits that tells the Central Processing Unit (CPU) exactly *what* operation to execute, such as an addition, a data load, or a jump. The Operand field is equally crucial as it specifies *where* the data for the operation resides or *what* the data is. This field can contain an immediate constant value, the unique identification code of a processor register, or a memory address. In essence, the OPCODE defines the action, and the Operand defines the target of that action, making the operand a required companion for most machine instructions to be meaningful and executable.

The incorrect option is (1):
The term "Operators" is functionally equivalent to the OPCODE itself in this context. The OPCODE specifies the operation—the mathematical or logical action—which is performed by the CPU. Therefore, the machine instruction consists of the operator (the OPCODE) and the object it operates upon (the Operand). To state that the instruction consists of the OPCODE and "Operators" would be redundant, as the OPCODE field is already defining the specific operator for the instruction.

The incorrect option is (3):
A "Variable" is a conceptual feature of high-level programming languages, serving as a symbolic name for a memory location. Machine-level instructions, however, operate directly on hardware resources without using these human-readable names. The instruction format does not reserve a field for a "variable name." Instead, the Operand field is used to hold the binary encoding of the raw physical address or the register number where the variable's value is stored, which is what the CPU requires.

The incorrect option is (4):
A "Function" is a software concept representing a subroutine or block of code designed to perform a specific task, and it is made up of a *sequence* of multiple, individual machine-level instructions. The instruction format, by definition, describes the internal structure and layout of a *single* instruction. Since a function is a composite of many instructions, it cannot be a constituent field within the format of just one machine instruction.