Which type of error may be significant enough to affect the results of a survey significantly?

Systematic error refers to consistent, repeatable errors that occur due to a flaw in the measurement system, such as calibration issues with instruments or biases in methodology. These errors can affect survey results significantly because they do not cancel out with repeated measurements as random errors might. Instead, they introduce a consistent bias in the data that can lead to inaccurate conclusions if not identified and corrected.

For instance, if a leveling instrument is consistently off due to improper calibration, all measurements taken will be offset by the same amount, which skews the final results. This makes systematic error particularly important to detect and mitigate in surveying since it can lead to significant deviations from true values.

In contrast, blunders may arise from human mistakes or miscalculations and while they can lead to significant deviations, they are typically isolated incidents rather than ongoing issues impacting all measurements. Random errors, on the other hand, are variable and can average out over many observations, thus having less influence on results than systematic errors. Instrument errors can also be a part of systematic errors but are considered more specific to the equipment rather than the inherent biases that systematic errors introduce.