context:  Following their home loss to the Packers, the Rams flew to Candlestick Park for a Week 4 NFC West duel with their hated rival, the San Francisco 49ers.  Due to an injury to Marc Bulger, quarterback Kyle Boller got the start. After a scoreless first quarter, St. Louis' seasonal struggles continued on the 49ers' second punt of the game.  The ball would hit backup cornerback Quincy Butler's foot and roll into the endzone where backup Niners linebacker Scott McKillop would land on it for a touchdown.  San Francisco would continue its dominating run in the third quarter with quarterback Shaun Hill hooking up on a 13-yard touchdown pass to tight end Vernon Davis, followed by linebacker Patrick Willis returning an interception 23 yards for a touchdown.  The 49ers would wrap up their victory march in the fourth quarter with Hill finding wide receiver Josh Morgan on a 24-yard touchdown pass, followed by defensive tackle Ray McDonald returning a fumble 11 yards for a touchdown. With their second shutout loss of the season, the Rams fell to 0-4.
question: How many yards was the longest passing touchdown?
answer: 24