Fifth Harmony performs on “X Factor.” (Ray Mickshaw /Fox)

Tonight on “The X Factor” we learn which three of the four surviving acts will go on to next week’s final shot at that $5 million prize.

Straight off, we’re going to send one act home. Judge/Mentor LA “I Am Not Enhancing My Cred By Coaching A Chubby Middle-Aged Country Singer” Reid has told “Access Hollywood” that he’s not returning next season.

Back on stage, the remaining X-testants have been assembled:

*Chubby Middle Aged Country Singer Tate Stevens…

*Boy band Emblem3, anointed the next One Direction by Supreme Judge Simon “Did I Mention I Discovered One Direction” Cowell…

*Carly Rose Sonnenclar, the 13-year-old with the Broadway voice…

*Fifth Harmony, the girl group put together by Simon from five rejected soloist X-auditioners.

Ko-Hosts Khloe Kardashian-Odom and Mario Lopez wind up to send the first act through to the finals and it’s…Great Destiny’s Child’s Ghost! It’s the girl group Fifth Harmony!

This is a shocker because they’ve given a series of pleasant though utterly forgettable performances, with the exception of last night’s playful “Anything Could Happen” staged as a Mad Hatter’s Tea Party.

Next to go through: Tate Stevens. No surprise here, he’s been in first or second place in the voting for weeks now.

That leaves Carly Rose vs. the Emblem3 boys. We think it’s not looking good for little Carly Rose, given her disquietingly amped up versions of Elton John’s “Your Song” and John Lenon’s “Imagine” Wednesday night, during which she seemed to cross the line from cute to creepily mechanical under the firm hand of overbearing stage parents and mentor Britney “Trust Me I Used to Be a Child Star, Too” Spears.

On the other hand, Emblem3 wandered farther off into their musical identity crisis with Peter Frampton and Beatles songs Wednesday night, under the firm hand of Simon.

Before we get a decision, we get Bruno Mars singing his just released “Lock Down Heaven”. Good to know the X-producers give equal treatment to visiting stars – like the amateur X-performers, Bruno too gets drowned out by the usual messy sound mixing.

Back to results. Going home is…Emblem3!

Simon looks grim. In grief, he seems even puffier than usual.

Not so the three Emblems, who take it philosophically. “I know you guys voted your butts off,” says one to their fans. “It’s all good. We love you and we’re going to continue to move it.”

Roll tape of the boys’ journey on the show, starting with their genuinely enthusiastic and engaging early work, becoming progressively more contrived under Simon’s One Directional mentorship. It’s kinda sad.

Next week: the final sing-off with entertainment by, of course, One Direction.