It is really strange that casper isn't playing his usual tricks, eli thought as she suspiciously eyed casper, who sat quietly in a corner. usually, when casper realized that eli and mom were going to the supermarket, he would start barking till they gave him a treat. today, surprisingly, casper only gave them a mischievous look. as eli and mom began getting ready to leave the house, mom asked eli if she had seen her red shoes, and when eli said no, the two began looking around the house for the shoes. soon, eli spotted casper with with one red shoe in his mouth as he darted out into the backyard. mom and eli laughed as they realized casper's new trick to prevent them from going out.

which is the best summary of the passage?
a.
eli finds casper's quiet behavior very unusual. later, when eli’s mom loses her red shoes, eli notices casper’s mischievous look and realizes that casper must have hidden the shoe somewhere so that she and her mother cannot go out to the supermarket.
b.
eli and her mother begin to look for a missing red shoe but are unable to find it anywhere. after a while, eli spots her dog casper playing with the red shoe outside, and realizes that casper has found a new game with which to trouble them.
c.
eli wonders why casper is quiet, as she her mother find a red shoe to go to the supermarket. later, eli sees casper with the one red shoe as he darts outside and understands that this is casper’s new way of stopping them from leaving.
d.
eli and her mother are about to head out to the supermarket when their dog casper begins barking. eli gives him a treat and promises that they will be back soon and begins looking for red shoes.