Claire A

Out of the two options, the Claire A scenario is canon.

Story
Claire Redfield rides into Raccoon City on her motorbike looking for her brother Chris. When she searches a restaurant, she is approached by a Zombie. Heading for the back door, she is introduced to another survivor; Leon S. Kennedy.

The police cruiser they commandeer crashes head-on into a lamp post and the two get out of the car just in time to escape the impact of a fuel truck with the cruiser.

Whilst on her way to the Police Department, Claire stumbles upon a third survivor; gunshop owner Robert Kendo. He however, is soon devoured by Zombies leaving Claire on her own again.

Claire encounters Leon again in the S.T.A.R.S. Office. He tells her that Chris had left town the month earlier. He hands her a radio before the two separate again.

Claire encounters a fourth and fifth survivor; Sherry Birkin and Brian Irons. Claire and Sherry later follow Irons' route down a secret room in his office. There, Claire witnesses a monster burst from Irons chest. Upon defeating the creature, Claire and Sherry explore the sewers and end up in the labs where the G-Virus was created, where she sherry, and Leon end up escaping in the train.