In investigating the cause of thinning hair, which of the following questions needs to be asked? a. Is the diet deficient in proteins? b. Is the person taking megadoses of vitamin C? c. Has the person...

In investigating the cause of thinning hair, which of the following questions needs to be asked?

a. Is the diet deficient in proteins?

b. Is the person taking megadoses of vitamin C?

c. Has the person been exposed to excessive radiation?

d. Has the person recently suffered severe emotional trauma?