Answer:
b. It would help to know the dowser's age and affiliation with other dowsers.
Step-by-step explanation:
A "dowser" is a person who claims have some supernatural powers and claims to have the ability to find something buried inside the earth without the use of any scientific tools and equipment.
A "charlatan" is a term given to person who falsely claim that one possess a special type of skill or knowledge.
All the options a). , c). and d). helps to evaluate that the dowser is a charlatan.
Only option b). favors the condition that the dowser is a charlatan.
Hence the answer is option
b. It would help to know the dowser's age and affiliation with other dowsers.