Concept:The phrase "hair stood on end" is an idiom that means extreme fear or fright.Explanation:When a person is very afraid, the body may react physically, such as hair rising on end.Hearing gun-shots is a sudden and terrifying sound for anyone, especially for an old woman.Thus, the expression shows that she was scared, not crying, inactive, or merely worried.So the correct meaning is "was frightened."Answer:C. was frightened.