She was much taller than the other girls. Her mannerisms seemed more graceful to Charlie. When she spoke, her words were marked by a slight lilt, which Charlie found endearing.

Characterization.

Explanation:

Characterization is a literary device that an author or writer uses to describe a character's trait and feature. A writer would usually introduce a character through direct characterization and indirect characterization.

In Direct Characterization, the author directly tells the trait or personality of the character.

In indirect characterization, a character is described by revealing his/her personality.

In the given case, the author has used the device of characterization to describe the girl indirectly through her looks.

So, the correct answer is characterization.