42. In a classic experiment, "Little Albert," a very young boy, was conditioned to be afraid of a rat. He also became fearful of white furry rabbits and bearded men. This is an example of

In a classic experiment, "Little Albert," a very young boy, was conditioned to be afraid of a rat. He also became fearful of white furry rabbits and bearded men. This is an example of

1. spontaneous recovery.
2. higher-order conditioning.
3. extinction.
4. stimulus generalization.