conducted research to test his theory that people with beautiful, legible handwriting are friendly and popular, whereas people with unreadable handwriting are unfriendly and unpopular. His premise was subtly communicated to the participants of his research. As a result, all his participants produced samples of beautiful, legible handwriting. Naveen's research most likely suffered from

Demand characteristics bias(a type of response bias)

Explanation:

Demand characteristics bias occurs when participants in an experiment become aware of the hypothesis being tested and try to align their answers to support the hypothesis. When participants in research are aware that the answers they would produce to questions asked would make them seem bad, they might produce dishonest answers that would have a skewed effect on the research.  

The type of bias displayed by these participants who produced samples of beautiful, legible handwriting was based on the fact that they knew the hypothesis being tested and wanted to prove by their actions that the hypothesis was true. This made them produce samples that were not a true reflection of their personalities. This would definitely affect Naveen's research.

answer; rational if melanie values sleep more highly than the benefits she expects to receive from attending the class;