Question on Ciaffone and Reuben Book P77

[Ryendal]

It's the question number 4 in his quiz on NL holdem

"You pick up Ac9c in late position. The player on your right opens the pot for 100$. What do you do ?"

Answer " Fold "

Explanation " Your position relative to the raiser is the worst possible...Ac9c is a drawing hand requiring very favorable position to playing in a raised pot. "

Well, I don't understand, It seems we are in position, but Ciaffone write that it is the worst position.

Does someone could enlight me with this problem ?

Thank you