Which of the following statements is most appropriate?

a. Independence must be guarded at all costs and sufficient independence is needed to enable professional audit work to be carried out and acted on by management.

b. Independence cannot be guarded at all costs and only sufficient independence is needed to enable professional audit work to be carried out and acted on by management.

c. Independence cannot be guarded at all costs even though absolute independence is needed to enable professional audit work to be carried out and acted on by management.

d. Independence cannot be guarded at all costs and only sufficient independence is needed to enable professional audit work to be carried out even where it is not acted on by management.