Which belongs in the summary because it is an important event
caused by the main problem?
Problem: The miller needs a job and worries about
people's opinion of him.
A:The miller takes his son's place on the
donkey's back.
B:An older couple on power scooters
whizzes by the miller, his son, and their
donkey
C:A man complains that the father should
let the boy ride the donkey
D:The donkey walks even slower with the
son riding on its back.

It is 100% correct -I did it and it was correct.

A - The miller takes his son's place on the donkeys back.

Explanation:

Because, the miller was embarrassed when a couple commented  that a father should make his growing boy stronger by letting him walk so the miller decided to take his son's place on the donkey and let his son walk.

the third paragraph is your answer,

"but, in a larger sense, we can not dedicate — we can not consecrate — we can not hallow — this ground. the brave men, living and dead, who struggled here, have consecrated it, far above our poor power to add or detract. the world will little note, nor long remember what we say here, but it can never forget what they did here. it is for us the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. it is rather for us to be here dedicated to the great task remaining before us— that from these honored dead we take increased devotion to that cause for which they gave the last full measure of devotion—that we here highly resolve that these dead shall not have died in vain—that this nation, under god, shall have a new birth of freedom—and that government of the people, by the people, for the people, shall not perish from the earth. "