What is the main plot to Harry Potter?? Also what’s your house??

Which line from hopkins's "spring and fall: to a young child" includes an allusion to an ancient story? a. "it is margaret you mourn for" b. "it is the blight man was born for" c. "are you grieving / over goldengrove unleaving? " d. "now no matter, child, the name: / sorrow's springs are the same"