Anu is an impatient listener. she is too eager to react when told anything. In this sentence She refers who?
She in the sentence refers to 'who' (the subject in the sentence). It gives details that describe the subject further. In your sentence, it describes how Anu is eager to react.
She refers to Anu. Anu is an impatient listener. Anu is too eager to react when told anything.