is expanding its A3 lineup with a 4-door sedan that has just been caught testing by our spy photographer. Joining the 3-door hatchback and 5-door Sportback, the Audi A3 sedan will be looking to target the US and China where it will come up against the recently debuted Mercedes-Benz CLA
. We've been expecting the four-door sedan ever since Audi unveiled a near-production ready A3 Concept
at the 2011 Geneva Motor Show, and from these spy shots we can see plenty of styling similarities.