What is the process followed in the waterfall model?
1) Requirements analysis → Design checking → Implementation and unit testing → Integration and system testing → Maintenance regression testing
2) Design checking → Requirements analysis → Implementation and unit testing → Integration and system testing → Maintenance regression testing
3) Implementation and unit testing → Requirements analysis → Design checking → Integration and system testing → Maintenance regression testing
4) Requirements analysis → Implementation and unit testing → Design checking → Integration and system testing → Maintenance regression testing