Learning that is not directly observable is called

This is known as latent learning: learning that occurs but is not observable in behavior until there is a reason to demonstrate it. Latent learning also occurs in humans.

Explanation:

The right answer is D. Latent Learning. This type of learning is not visible or expressed by the person until a reinforcement occurs that drives the person to do what they have learned. For example, a young man makes a sandcastle when they go to the beach, when they ask him how he learned to remember that it was through a television program he saw years ago.