The relationship between the required understanding of the internal control structure and the preliminary audit strategy is that:

A. Normally, greater understanding is required when the lower assessed level of control risk approach is used.

B. Normally, greater understanding is required when the primarily substantive approach is used.

C. No understanding is required in the planning stage unless tests of controls are a planned part of the strategy.

D. Normally, less understanding is required when the lower assessed level of control risk approach is used.