Its A. With the family's P.O.V, we can fully see what was really going on.
This is an idea for you:
Mary, in the beginning of the book, is selfish, spoiled, and pampered, but she changes throughout the book with Dickon's and the robin's help. In turn, she helped Colin, who was the same as she was when she was younger. Her change helped her help others, like Colin, to become more out looking for others and help become more kind to others.
This is just my perspective. Hope it helps!
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1.) B. Folk art helps us understand history.
2.) A. Antenna.
3.) C. One result of our discussion