Which two of the following models will not be able to give the desired outcome if user’s participation is not involved?

Which two of the following models will not be able to give the desired outcome if user’s participation is not involved?

A. Waterfall & Spiral
B. RAD & Spiral
C. RAD & Waterfall
D. RAD & Prototyg

Explanation: Active Participation of user is involved in all the four phases of RAD model and in case of the Prototyg model we need user’s presence/involvement every time a new prototype is build or designed.