Question 1: Level, trend, and design limits
Which conclusion is best supported?
- The intervention demonstrated a functional relation because responding decreased.
- Responding decreased in level and showed a descending trend after intervention, but an A–B comparison alone does not demonstrate experimental control.
- Baseline was too variable to permit any comparison.
- The intervention produced an immediate zero level of responding.
Reveal the answer and rationale
Answer: B. The graph shows lower responding and a descending intervention trend. However, an A–B design provides a comparison without verification and replication, so it does not by itself demonstrate a functional relation. Option A overstates the evidence, C mischaracterizes the relatively stable baseline, and D does not match the data.
