I pick Elisha Cuthbert cos she's Canadian eh :p and she's smaller so I can relate to her :)or maybe I'm just jealous of Kate Upton and her big boobs , whatever :p
I'm against the idea to call a particular girl attractive. Maybe that's just me, but to me, all ladies are attractive and beautiful in their own way. Nothing more, nothing less , everyone in their own unique way.
But here in this question I would choose Miss Elisha Cuthbert
Because i feel better connection to her as i know her by one of my all the time favorite series called "24" while she was around 18-19 years old! Now she's 32 and seen so many movies by her over times.
And by the question i remembered something to share related to the topic, Back in 2002-3 / 24 / Season 2 / in a interview with Elisha Cuthbert, when she's been asked about work and process of the movie, she replayed in a funny manner, "It's been a hard work, especially for me, since I was the only one with breasts" lol!
I think it's Elisha.
Elisha Cuthbert, for sure.