Which of the following system and data conversion strategies provides the GREATEST redundancy?

A. Direct cutover

B. Pilot study

C. Phased approach

D. Parallel run

Explanation:

Parallel runs are the safest-though the most expensive-approach, because both the old and new systems are run, thus incurring what might appear to be double costs. Direct cutover is actually quite risky, since it does not provide for a shake down period nor does it provide an easy fallback option. Both a pilot study and a phased approach are performed incrementally, making rollback procedures difficult to execute.