Low Tips or Failing to Be Tipped at All Is

Low tips or failing to be tipped at all is interpreted by waitresses as

A) a consequence of the customer's being too cheap, too poor, or too ignorant to tip properly.
B) a personal failure on their part.
C) the fault of the restaurant for not making customers comfortable and happy enough to tip.
D) the result of a bad economy and hard times for working families.