Correct Answer: encourage

Solution : The correct option is the second option.

Explanation : The word dishearten means to cause someone to lose determination or confidence, while encourage means to give support, confidence, or hope. In the context of antonyms, encourage is the opposite of dishearten, as it implies providing positive motivation or upliftment.

The meanings of the other options are as follows:

1. Humble : This term means having or showing a modest or low estimate of one's importance.
2. Indispose: This term means to make someone unwilling or disinclined to do something.
3. Dampen: This term generally means to make something slightly wet or moist.

Therefore, the correct answer is encourage.