What is one potential limitation of questionnaire responses?

One significant limitation of questionnaire responses is that respondents may answer based on perceived expectations, also known as social desirability bias. This occurs when individuals provide answers they believe are more acceptable or favorable rather than their true feelings or intentions. For example, in surveys related to sensitive topics like health or social behavior, individuals might exaggerate positive behaviors or downplay negative ones, leading to skewed data that doesn’t accurately reflect reality. This bias can greatly affect the validity of the study's findings, as the information gathered may not represent authentic opinions or experiences.

In contrast, the other options highlight potential issues that are less relevant: the speed of data collection is usually not a major concern for questionnaires, the variety of responses can actually enhance the depth of qualitative analysis, and the accuracy of data being "too high" does not pose a practical limitation, as high accuracy is generally a desirable outcome in data collection.