Dakota Fanning had a tough decision to make when she was asked to choose which Olsen twin she was better friends with.

Did Mary-Kate Olsen Get Plastic Surgery?

On Wednesday, Us Weekly posted a clip from Watch What Happens Live when Fanning made a guest appearance. When a caller asked her about her friendship with Mary-Kate and Ashley Olsen, the actress needed to answer which one she's closer to as well as who has a better fashion sense.

The 21-year-old hesitated a little on this question mainly because there's a certain member of the Olsen family who she's actually much closer to.

Mary-Kate & Ashley Olsen Inspire A DJ

"Their younger sister Lizzie [Elizabeth Olsen] is who I know the best," Fanning said. "We went to the same high school, we have a lot of mutual friends, and we did a film together [Very Good Girls]."

As for the twin sisters, the Coraline star couldn't decide between them on who she would choose as a closer friend.

"I've only truly met them a couple of times," Fanning admitted. "I don't think I know them well enough to answer that question."

When it comes to the decision of which sister has the better fashion sense, the actress's response was, "Both of them are totally lovely."

Mary-Kate and Ashley might be known for their clothing line, but they became sensations in the entertainment industry as child stars in plenty of films as well as the popular series Full House.

Tags: Mary-Kate and Ashley Olsen Dakota Fanning