Assembly section conventions: In a sectional view of an assembly, standard drafting practice is that fasteners and similar hardware (for example, bolts, nuts, washers, shafts, and keys) are typically shown unsectioned (not hatched) even when the cutting plane passes through them. Confirm this convention.

Introduction / Context:
Sectional views are core to working drawings because they reveal interior relationships without visual clutter. A widely taught convention is that standard fasteners and similar hardware are not hatched when shown in assembly sections. This question checks your understanding of that convention and why it exists in professional drafting practice.

Given Data / Assumptions:

• The view in question is a section of an assembly, not a detail of a single part.
• The cutting plane passes through items such as bolts, nuts, washers, shafts, and keys.
• The goal is readability and rapid interpretation by machinists and assemblers.

Concept / Approach:
Hatching communicates “this material is cut.” However, in assemblies, indiscriminate hatching of every cut component can obscure fit and function. Longstanding conventions leave standard fasteners and rotating shafts unsectioned to emphasize the major mating parts and interfaces. Keys are often outlined without hatch so their position is clear against the shaft and hub hatching behind them. The convention improves legibility and reduces confusion about how pieces fit together.

Step-by-Step Solution:

Verification / Alternative check:
Compare a heavily hatched assembly against one using the convention. The latter is easier to interpret: bolt shanks, nuts, and keys read instantly without the distraction of dense hatching patterns.

Why Other Options Are Wrong:

• Hatching every cut object (option B) reduces clarity.
• Limiting the rule to nonmetallic parts (option C) is incorrect; material is not the criterion.
• Removing fasteners completely (option D) loses essential information.
• Exempting only shafts (option E) is too narrow; nuts and keys are also typically unsectioned.

Common Pitfalls:
Confusing single-part section rules with assembly conventions; over-hatching; forgetting to differentiate keys from the surrounding shaft and hub materials.

Final Answer:
Correct: these items are typically left unsectioned in assembly sections