Suppose You Obtained the Following Results in an ABAB Design

Multiple Choice

Suppose you obtained the following results in an ABAB design assessing the effectiveness of family therapy in reducing a child's temper tantrums.Which interpretation(s) is(are) plausible?
$$\begin{array}{l}\text { Number of tantrums per day: }\\\begin{array} { l l l l l l l } \text { A: } & 4 & 5 & 4 & 5 & 4 & 4 \\\text { B: } & 1 & 1 & 1 & 0 & 0 & 0 \\\text { A2: } & 0 & 0 & 0 & 0 & 0 & 0 \\\text { B2: } & 0 & 0 & 0 & 0 & 0 & 0\end{array}\end{array}$$

A) History could have caused the change.
B) The intervention may have been effective, but with irreversible effects.
C) History could have caused the change or the intervention may have been effective, but with irreversible effects.
D) none of these.