In auxiliary-view construction for descriptive geometry and drafting, distances are transferred either perpendicular to the reference (fold) line or parallel to the projection (projector) lines so that sizes are preserved between related views. Decide whether the statement is correct.

Introduction / Context:
In technical drawing, especially when creating auxiliary views, we frequently transfer distances between related views. The rule-of-thumb is that measurements are carried along directions that preserve true size with respect to the governing reference construction. The statement claims that measurements are always made at right angles to the reference lines or parallel to the projection lines. We evaluate why this practice is correct in standard auxiliary-view workflows.

Given Data / Assumptions:

• Reference line (fold line) separates the parent view from its auxiliary view.
• Projection lines (projectors) are drawn perpendicular to the reference line.
• Goal: preserve true distances when establishing points/edges in the auxiliary.

Concept / Approach:
When constructing an auxiliary, points are projected perpendicular to the reference line (i.e., parallel to projectors). Measured offsets are then carried perpendicular to projectors (i.e., along the reference line) or directly parallel to projectors, depending on the step, to avoid scale errors. This orthogonality ensures geometric fidelity between views.

Step-by-Step Solution:
1) Establish the reference line for the auxiliary relative to the parent view.2) Project key points from the parent view by drawing lines perpendicular to the reference line (parallel to projectors).3) Transfer required distances either perpendicular to the reference line or parallel to the projectors to place true-size features.4) Connect projected points to complete edges and contours in the auxiliary view.

Verification / Alternative check:
Any attempt to transfer a length at an oblique angle to both the reference and projector lines distorts scale, producing incorrect geometry. Working strictly perpendicular/parallel prevents distortion.

Why Other Options Are Wrong:
“Incorrect”: Ignores the orthogonality that preserves true distances.“Only perpendicular transfers are valid” / “Only parallel transfers are valid”: Both directions are used at different steps of the construction.

Common Pitfalls:
Tilting transfer lines slightly; using a non-square triangle; forgetting that projectors are perpendicular to the reference line.

Final Answer:
Correct