The question that narrows the focus of his research is:
"What is the relationship between music education and academic achievement? (Option D)
The focus of research is the critical information that the researcher seeks to clarify.
Research usually involves a hypothesis. This hypothesis must be properly formatted and investigated.
When the hypothesis is disproved, it is said to be null. Hence, the question that clarifies the hypothesis of the research above is:
"What is the relationship between music education and academic achievement?"
Learn more about research at:
https://brainly.com/question/968894
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