Technical Drawing — The Offset tool is useful when setting up an auxiliary view because parallel construction lines (or edges) are needed to project points from the principal view onto the auxiliary projection plane.

Introduction / Context:
Auxiliary views commonly require projecting geometry from a principal view to a new plane that is parallel to an inclined surface. CAD’s Offset tool rapidly creates parallel lines at controlled distances, providing clean projectors and construction references.

Given Data / Assumptions:

• An inclined surface must be shown in true shape using an auxiliary view.
• Projectors from the principal view to the auxiliary plane must remain parallel.
• Offset can create those parallel projectors and boundary guides quickly.

Concept / Approach:
Orthographic projection relies on parallel projectors. By offsetting edges, centerlines, or construction baselines, you obtain parallel references that help transfer distances and locate points accurately onto the auxiliary plane.

Step-by-Step Solution:
1) Identify key edges/axes in the principal view.2) Use Offset to create equally spaced projectors or guide lines.3) Mark transferred distances along these guides on the auxiliary plane.4) Trace the auxiliary profile and add dimensions on that view.

Verification / Alternative check:
Measure between original and offset projectors; they should be consistent. Check that transferred point-to-point distances match the model’s true lengths within the plane.

Why Other Options Are Wrong:
Offset works with lines, arcs, and polylines, not just circles; it is widely used beyond architecture; it fully supports orthographic projection rather than breaking it.

Common Pitfalls:
Offsetting from erroneous references; mixing construction and object layers; forgetting to purge temporary guides before plotting.

Final Answer:
Correct