It would be All the nurses I met greeted e with their best smile. Because you are not specifying whether the person or people, are males, or females.
D: summarizes the significance
He was impressed by the river chariots in Hannibal, and wanted to become a steamboat captain. Mark Twain even got an apprenticeship with a steamboat captain.
In Mark Twain's writings of the Mississippi river that borders Hannibal, he claimed he was extremely impressed and fascinated by the Mississippi river.
For more about Hannibal, Missouri you can visit https://hannibal-mo.gov
The best answer there would have to be A. i know cause i have read sherlock holms for most of my life