April Fool!

Question: Is it…

– April Fool, (Singular?)

– April Fool’s, (Singular Possessive?)

– April Fools, (Plural?) or…

– April Fools’? (Plural-Possessive?)

Anyway, so far it looks like MeFi is under new management, Jish has gone MeFi Blue, Rich has gotten hitched (is that for real?), Google uses pigeons, and Duane has seen the light on the unholy evil leaven of alcohol.