It would be the location that is the biggest clue
I think it is A. was waving at the flag. This is just my opinion is I may be wrong. Please feel free to correct me in the comments. Have a nice day!
Answer:
The answer is: indicate why Professor Hodous should be considered an expert on Buddhism
Explanation:
When learning an educational book on a certain topic, it is essential to be familiar with the author's level of expertise, in order to gain valid information. One's level of expertise can be judged based on his knowledge or experience. Although undoubtedly immense, we can not draw definite conclusions about the range of professor's knowledge from this excerpt. However, from the information about his sixteen years long missionary services in the important Buddhism center, we can certainly claim that professor Hodous is filled with experience on this topic.