Morton Hunt's Data-Gathering for His Book Titled Sexual Behavior in the 1970s

Morton Hunt's data-gathering for his book titled Sexual behavior in the 1970s was flawed because:

A) the study was done using subjects from a very small geographic area.
B) over half of the subjects found the apparatus on their sexual organs to be uncomfortable.
C) he coerced people into participating.
D) he included only those with listed phone numbers.
E) he slanted his results to favor the government agency funding his research.