In computer architecture and assembly language, what is the key difference between mnemonic codes and machine codes? Provide the most accurate description comparing their human readability and representation.

Introduction / Context:
Assembly programming bridges human intent and hardware execution. The same instruction can be expressed in two forms: a human-readable shorthand known as a mnemonic, and a hardware-executable machine code composed of binary patterns. Understanding this distinction is foundational for anyone working with assemblers, disassemblers, or embedded firmware.

Given Data / Assumptions:

• A processor executes binary opcodes and operands.
• Assembly language exposes those operations with short words such as MOV, ADD, JMP.
• An assembler converts mnemonics to numeric opcodes; a disassembler does the reverse best-effort.

Concept / Approach:
Machine code is the literal binary (or hex) encoding that a CPU fetches and executes. Mnemonics are symbolic names for those opcodes that humans can read, write, and reason about. The assembler maps each mnemonic plus addressing mode and operands to a specific opcode pattern and operand fields. The mapping is architecture specific, which is why mnemonics differ across CPU families even for similar operations.

Step-by-Step Solution:
Identify what hardware consumes: binary instruction words (machine codes).Identify what programmers commonly write: symbolic instructions (mnemonics) like MOV R1, R2.State the translation: assembler converts mnemonics to machine code and resolves labels to addresses.Conclude: machine codes are binary; mnemonics are shorthand English tokens that represent them.

Verification / Alternative check:
Examine an object file or a hex dump. Each instruction appears as bytes (for example, 0xB8 0x34 0x12). A disassembler shows the corresponding mnemonic (for example, MOV AX,1234h). This demonstrates the one-to-one mapping between human-readable mnemonics and binary encodings for a given architecture.

Why Other Options Are Wrong:
There is no difference: false; representation and audience differ.

Machine codes as shorthand English or high level: incorrect; machine code is binary.

Compiler to C: unrelated to assembly mnemonics and machine encodings.

Common Pitfalls:
Confusing assembly with high-level languages or assuming the same mnemonics across architectures. Mnemonic sets vary; the binary is always the CPU's ground truth.

Final Answer:
Machine codes are in binary, mnemonic codes are in shorthand English.