Ashley, a psychology major, remarks that she has become interested in the study of intelligence. In other words, Ashley is interested in:

the capacity to understand the world, think rationally, and use resources effectively.

Explanation:

Intelligence refers to higher level abilities, the ability to learn, being creative, having an emotional knowledge, and ability to adapt to different scenarios.

Since Ashley, a psychology major, remarks that she has become interested in the study of intelligence, then Ashley is interested in the capacity to understand the world, think rationally, and use resources effectively.