Assertion–Reason (Instruction Length in 8085): Making source and destination addresses implicit reduces instruction length; this is because the 8085 has only three addressing modes.

Introduction / Context:Instruction encoding length depends heavily on addressing modes. If operands (source/destination) are implied, fewer bits are required, resulting in shorter opcodes—important in 8-bit CPUs like the 8085.

Given Data / Assumptions:

• Assertion: Implicit addressing reduces instruction length.
• Reason: 8085 supposedly has only 3 addressing modes.
• Real addressing modes of 8085 include immediate, register, direct, register indirect, and implied (among others like RST).

Concept / Approach:Implicit (implied) addressing hard-codes the operand/register in the instruction definition, eliminating the need to encode register fields or addresses. This indeed reduces the number of bits. However, the stated reason is factually incorrect because the 8085 supports more than three addressing modes.

Step-by-Step Solution:

Verification / Alternative check:Look up any 8085 programming manual and count distinct addressing styles used by instructions like MVI (immediate), MOV (register), LXI (immediate 16-bit), STA/LDA (direct), and instructions such as CMA (implied).

Why Other Options Are Wrong:

Common Pitfalls:

Final Answer: