The Major Disadvantage of Rate Regulation of Natural Monopolies Is

The major disadvantage of rate regulation of natural monopolies is that:

A) natural monopolists spend too much time lobbying for higher rates.
B) unlike a competitive firm, the natural monopoly has too much incentive to increase efficiency.
C) the regulatory bureaucracy grinds slowly and generates regulatory lags.
D) state public service commissions are poorly staffed and supervised.
E) natural monopolists spend too much money on philanthropic activities.