Which one of the following statements is correct? Select one: a. The one-third correspondent allowance is payable on the fees of the attorney's practice including advocate costs and sheriff costs. b. The collection commission is calculated on any expenses that are paid directly to third parties. c. A minimum of one-third of the fees (professional and collection commission) charged must be granted. d. The instructed attorney may grant a correspondence allowance of a maximum of one-third of the fees (professional and collection commission)