Policies Such as Rent Control and Import Quotas Persist in Spite

Policies such as rent control and import quotas persist in spite of the fact that economists are virtually united in their opposition to such policies,probably because

A) economists have not yet convinced the general public that the policies are undesirable.
B) economists engage in positive analysis, not normative analysis.
C) economists have values that are different from the values of most non-economists.
D) economists' theories are not easily confirmed or refuted in laboratory analysis.