HMS, BM EQ-Bank 409 MC

A student investigated the effects of aerobic training on perceived exertion levels using RPE scales. However, the student discovered that different participants were given different instructions on how to use the scale, and some participants weren't familiar with the 6-20 rating system.

Which statement best describes the issue with this data collection approach?

1. The data lacks reliability because participants used inconsistent rating methods.
2. The data lacks validity because RPE scales don't measure physiological responses.
3. The data lacks credibility because perceived exertion is too subjective to measure.
4. The data lacks accuracy because the aerobic training program was inappropriate.