The addressing mode, in which the instructions have no source and destination operands, is register specific instructions.


In computer architecture and assembly language programming, addressing modes define how the operands of an instruction are specified. The addressing mode determines where the operands are located and how they are accessed. Different addressing modes have different syntax and semantics.


- Register instructions refer to instructions that operate on registers.
- In these instructions, the operands are specified implicitly by referring to registers.
- For example, the instruction "ADD R1, R2, R3" adds the values in registers R2 and R3 and stores the result in register R1.
- Register instructions do not fit the description of the addressing mode where there are no source and destination operands specified.


- Direct addressing is an addressing mode where the operand is specified directly as a memory address.
- For example, the instruction "LOAD R1, 100" loads the value from memory location 100 into register R1.
- Direct addressing involves specifying the memory address as an operand and does not fit the description of the addressing mode where there are no source and destination operands specified.


- Indirect addressing is an addressing mode where the operand is specified as a memory address stored in a register.
- For example, the instruction "LOAD R1, (R2)" loads the value from the memory address stored in register R2 into register R1.
- Indirect addressing involves specifying a register that contains the memory address and does not fit the description of the addressing mode where there are no source and destination operands specified.


- Register specific instructions are a special type of instructions where the instruction itself specifies the source and destination registers implicitly.
- These instructions do not require explicit source and destination operands to be specified.
- The source and destination registers are predetermined for each specific instruction.
- For example, the instruction "INC" increments the value in a specific register without explicitly specifying the source and destination registers.
- Register specific instructions fit the description of the addressing mode where there are no source and destination operands specified.

Therefore, the correct answer is option 'B' - register specific instructions.