FDA has responsibility to .
A. oversee the purity, quality, safety, usefulness and related characteristics of nation's food
B. oversee the purity, quality, safety, usefulness and related characteristics of nation's drug
C. oversee the purity, quality, saftety, usefulness and related characteristics of nation's cosmetics
D. all of the above
"Spot check"(in Para. 6) means .
A. pick out random samples
B. pick out all of samples
C. pick out specific samples
D. choose good smples to analysis