Answer:
a. Undercoverage bias
Explanation:
Based on the information provided within the question it can be said that the bias being mentioned is Undercoverage bias. This refers to when a population of a sample are not being represented correctly, which in this scenario is because these people cannot be contacted. Therefore the correct bias that results from this is Undercoverage bias.
Perhaps U should start with A header
Answer:
Performance appraisal
Explanation:
Performance appraisal is a systematic review of a person’swork and achievements over a recent period, usually leading toplans for the future.
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