The Apollo program was a series of space missions conducted by NASA in the $1960$s and early $1970$s$.$ Its primary goal was to land humans on the Moon and safely return them to Earth. The program involved the development of complex information systems to support various aspects of space exploration. NASA started by defining detailed requirements for the Apollo program, including mission objectives, spacecraft specifications, and astronaut training needs. These requirements were documented and used as the foundation for subsequent phases. The engineers then designed the Apollo spacecraft, lunar module, and command module. Detailed blueprints, schematics, and technical specifications were created. With rigorous quality control and extensive testing, teams of engineers, scientists, and technicians constructed the spacecraft and its associated systems based on the design specifications. The various subsystems were then integrated into the complete spacecraft, and the command module, lunar module, and Saturn V rocket were assembled. After the deployment of each Apollo mission, NASA analyzed data, reviewed mission success, and identified areas for improvement. Lessons learned were incorporated into subsequent missions. What system development approach did NASA use for the Apollo program?

Question $30$ options:

a$)$

Lean Software Development

b$)$

The Waterfall Model

c$)$

Extreme Programming

d$)$

Scrum