Eric and francine were at the library. they had a big report due in school, and they wanted to get as much research done as possible. neither one of them was paying attention to the sky getting darker and darker. it was really late.
"eric, i think i found a great article for your paper while i was looking for something else," francine said. "i can print it out, if you want."
", that would be great," eric said. "i could use one more article."
all of a sudden, the lights started going out in the library. the whole first floor was dark. eric and francine looked over the railing on the third floor. not one person was in the library.
"do you think they forgot we came up here? " francine asked. "we have been pretty quiet for a while."
"no, they always check to make sure everyone is gone," eric said. "the librarian is probably just trying to tell us it's time to go. let's grab our stuff and go downstairs."
eric and francine picked up their books and papers and walked slowly down the stairs. it was so dark, francine was sure she would fall down. when they reached the front, the librarian was not at the desk. eric called many times, but no one answered. finally, francine walked over to try the door.
"it's locked! " she said. "we are stuck in the library! "

which of the following best summarizes the story?
a.
eric and francine were studying on the third floor when the lights started going out. eric and francine called to the librarian but nobody answered.
b.
eric told francine that someone always checks to make sure everyone left. eric and francine picked up their books and papers and went downstairs.
c.
francine found an article for eric to use while she was doing research. then, eric and francine saw that there were no other people in the library.
d.
eric and francine were doing research late one night at the library. the lights started going out, and they realized that they were locked in the library.