Explanation:
Preparedness tests would involve simulation of the entire test in phases and help the team better understand and prepare for the actual test scenario. Options B, C and D are not cost-effective ways to establish plan effectiveness. Paper tests in a walk-through do not include simulation and so there is less learning and it is difficult to obtain evidence that the team has understood the test plan. Option D is not recommended in most cases. Option C would require an approval from management is not easy or practical to test in most scenarios and may itself trigger a disaster.