Now I Know My ABC's...

Eh. Bee. See. Dee. Ee. Eff. Gee. Eche. Eye. Jay. Kay. El. Em. En. Oh. Pee. Cue. Are. Es. Tee. You. Vee. Double-You. Ex. Why. Zee.

And thus we see that “e” is the most common letter in the alphabet.