Which of the following presumptions is least likely to relate to the reliability of audit evidence? 

a. The more effective internal control, the more assurance it provides about the accounting data and financial statements. 

b. An auditor’s opinion is formed within a reasonable time to achieve a balance between benefit and cost. 

c. Evidence obtained from independent sources outside the entity is more reliable than evidence secured solely within the entity.

d. The independent auditor’s direct personal knowledge obtained through observation and inspection is more persuasive than information obtained indirectly.