According to NIST SP 800-64 Rev 2 (withdrawn) the system development life cycle is broken down into five phases. Which of the following is not one of the five phases? Response:

Implementation/Assessment is one of the five phases in NIST SP 800-64 Rev 2's SDLC.

"Testing" is not listed as one of the five distinct phases in NIST SP 800-64 Rev 2's System Development Life Cycle model; testing is typically an integral activity performed during the Implementation/Assessment phase. The five phases are Initiation, Acquisition/Development, Implementation/Assessment, Operation/Maintenance, and Sunset (Disposal).

Initiation is one of the five phases in NIST SP 800-64 Rev 2's SDLC.

Acquisition/Development is one of the five phases in NIST SP 800-64 Rev 2's SDLC.

Operation/Maintenance is one of the five phases in NIST SP 800-64 Rev 2's SDLC.

Sunset (Disposal) is one of the five phases in NIST SP 800-64 Rev 2's SDLC.