Answer:
a. Cross-sectional design
Explanation:
Cross-sectional design -
It is the type of research design , where the study require data from all the fields of interest , for analysis , is known as cross - sectional design.
In this type of method , every bit and piece of information is gathered from the research topic and then analysed , in order to have a proper and brief knowledge of the topic.
Hence, from the question,
The research method adapted by the professor Grant is the Cross-sectional design.
