Which of the Following Is True Regarding the Opportunity Costs

Which of the following is true regarding the opportunity costs of holding cash and the size of the cash balance held by a firm?

A) There is no relationship between cash balances and opportunity costs.
B) The higher the cash balance, the higher the opportunity cost.
C) Opportunity costs are minimized at the optimal cash balance.
D) If a firm can reduce its collection float, opportunity costs will fall and the optimal cash balance for the firm will be increased.
E) If a firm can reduce its collection float, opportunity costs will rise and the optimal cash balance for the firm will be decreased.