Errors and mistakes in surveying: Mistakes that can produce a very serious effect on final results most commonly arise due to which of the following?

Introduction / Context:
Measurement quality depends not only on instrument precision and method but also on human factors. Random errors can be mitigated statistically, but mistakes (blunders) can severely corrupt results if not detected and corrected through good practice and redundancy.

Given Data / Assumptions:

• Mistakes are preventable human errors, not random noise.
• They include misreadings, transpositions, misidentification of points, and incorrect instrument setup.
• We aim to identify their usual origins.

Concept / Approach:

Mistakes typically stem from human factors such as inattention (distraction, fatigue), inexperience (insufficient training to recognize pitfalls), and carelessness (haste, poor checking). Robust field procedures, check measurements, and standardized note-keeping are critical defenses. Therefore, all listed causes contribute materially to serious mistakes in surveying.

Step-by-Step Solution:

Verification / Alternative check:

Field QA/QC manuals emphasize training, rest, double-entry checks, and independent checks specifically to combat these human-factor sources.

Why Other Options Are Wrong:

Picking any single cause ignores the multifactorial nature of mistakes; “None” is plainly incorrect.

Common Pitfalls:

Confusing mistakes with random errors; assuming instrument accuracy alone prevents blunders.

Final Answer:

All of these