Suppose that you have two alternative systems $($ A and $B).$ Both systems provide the same features and allow users to complete the same tasks. System A can complete the tasks faster with a minimal number of steps. Therefore, we can say tha

A$.$ System $A$ is more effective, but $B$ is more efficient.

B$.$ System A and System B are both effective, but A is more efficient.

C$.$ System A and $5$ystem B are both effecient, but A is more effective.

D$.5$ ystem A and $B$ are both more effective, but B is more efficient.