To Understand an Example, You Need to Understand the Logic

To understand an example, you need to understand the logic behind the experiment that serves as the example. Morphine tolerance in the example in Chapter 1 would be shown when

A) paw-lick latencies decrease over time with repeated injections of morphine.
B) paw-lick latencies increase over time with repeated injections of morphine.
C) paw-lick latency do not vary as a function of time.
D) short latencies indicate reduced pain sensitivity.