Prove Your Love is my single favorite Christine song of all time. That drawn out "Aaah-ah-aaaaah" is just incredibly sexy. PYL is Christine at her sultriest.
My vote went to Come a Little Bit Closer. A nice song, but vanilla pudding compared to the other three, all of which I rank among Christine's best work.
"Just to hear Lindsey's voice with mine and Stevie's, I get goosebumps the size of chicken eggs." --CM