Retainer Search Firms Tend to Be More Popular with Corporate

Retainer search firms tend to be more popular with corporate human resource managers than do contingency search firms mainly because

A) retainer search firms are always less expensive
B) retainer search firms tend to be more aggressive
C) contingency search firms can be tempted to fill a position at any cost,regardless of fit
D) retainer search firms are more prevalent in most urban areas
E) contingency search firms are always two to three times more expensive than retainer firms