The research question 'How does exercise affect mental health?' is measurable and testable through empirical studies.
Out of the options provided, the research question 'How does exercise affect mental health?' is measurable and testable in a scientific manner. This question can be investigated through empirical studies where different exercise regimes can be implemented, and mental health metrics can be measured and compared to draw conclusions.
For example, researchers can conduct a study where individuals engage in various exercise routines, and their mental health status is assessed using standardized psychological assessments before and after the intervention. By analyzing the data gathered, researchers can quantify the impact of exercise on mental health.
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