"ELDERS." By Ryan McIlvain. Hogarth. $26.About five years ago, when the Best American Short Stories for 2008 were announced, I was disappointed to see among them one called "Missionaries," by Bradford Tice. This was maybe a small-minded reaction on my part. I had read the story more than once shortly after it was published in the Atlantic, and its selection for the annual anthology is not hard to understand: "Missionaries," which depicts two young men preaching the Mormon gospel in Knoxville, Tenn., is engaging and nicely crafted, with dramatic but believable scenes that build toward one character's ambiguous but striking epiphany. It's a pretty good short story. But it got Mormonism all wrong.