Select the most appropriate meaning of the underlined idiom in the given sentence.

Keep an eye on your sister as she might run away.

To watch over attentively

The most appropriate meaning of the underlined idiom in the given sentence is to watch over attentively.

The idiom "keep an eye on someone" is used to describe the act of watching someone closely and attentively, usually in order to make sure that they are safe or to prevent them from doing something wrong.

In the given sentence, the speaker is telling the other person to watch over their sister closely, because she might run away. This suggests that the speaker is worried about the sister's safety and wants to make sure that she does not run away.

The other options are not as appropriate meanings for the underlined idiom:

• To help someone: This is not the meaning of the idiom.
• To stop caring: This is not the meaning of the idiom.
• To act superior to someone: This is not the meaning of the idiom.