✓ Correct answer: C. 28 daysA candidate who fails the knowledge assessment must wait at least 28 days before being permitted to retake it.
Why the other options are incorrect:
• 7 days: A seven-day wait is not permitted under TfL's retake policy.
• 14 days: Fourteen days is shorter than the required 28-day minimum waiting period.
• 60 days: Sixty days exceeds the minimum waiting period that TfL requires.
• 6 months: Six months is far longer than TfL's stipulated minimum waiting period for knowledge test retakes.
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