Dan and Donna begin self-disclosing information about their dreams for the future, values, and religious beliefs, but they still spend a limited amount of time with one another. They are moving into which stage of relational escalation

Exploration.

Explanation:

Knapp's relationship model was theorised by Mark L. Knapp which defined the stages in a relationship that two people go through.

There are five stages in the relational escalation.

The stage at which Dan and Donna are exploration.

According to this stage of relational escalation, the couples begin to share the information in depth about each other with less physical contact and interaction.

In the given case, Dan and Donna have started to share information in-depth and spend less time with one another.

So, the correct answer is exploration.