Answer:
ОА
Sara was very mature for her age.
Step-by-step explanation:
She is described as having "an old look on her small face" and "thinking things about grown-up people and the world they belonged to".
"She felt as if she had lived a long, long time".
This implies that she is more mature than other children of her age. Sara is precocious and highly intelligent. She is also highly advanced in a number of ways, but that is not in excerpt given.