The question asks to identify the characteristics of RISC (Reduced Instruction Set Computing) architecture from the given options.

RISC Architecture Characteristics Analysis

Let's analyze each option:

• A. Large instruction set with many addressing modes: This is a characteristic of CISC (Complex Instruction Set Computing) architecture, not RISC. RISC aims to simplify the instruction set.
• B. Fixed instruction length: RISC architectures typically use a fixed instruction length. This simplifies instruction fetching and decoding, contributing to faster execution.
• C. Emphasis on software rather than hardware: RISC design philosophy relies on sophisticated compilers (software) to break down complex operations into simpler RISC instructions, optimizing execution. This contrasts with CISC's focus on complex hardware instructions.
• D. Simple instructions that execute in one cycle: A key goal of RISC is to have simple instructions that can be executed quickly, ideally within a single clock cycle. This pipelining efficiency is central to RISC performance.

Conclusion on RISC Features

Based on the analysis, the characteristics that accurately describe RISC architecture are:

• Fixed instruction length (B)
• Emphasis on software rather than hardware (C)
• Simple instructions that execute in one cycle (D)

Therefore, options B, C, and D are the correct characteristics of RISC architecture.