For a Treatment to Be Deemed Effective When Used in the Context

For a treatment to be deemed effective when used in the context of an A-B single-case design, what has to occur?

A) Behavior should change as the treatment is implemented
B) Behavior should return to baseline levels when the treatment is removed
C) When the treatment is removed, behavior should stay at the level that was created by the treatment rather than revert back to the baseline
D) The line representing the A phase should intersect with the line representing the B phase