Question

Henry Ford adapted the assembly line to make cars. The assembly line is an innovation in factory production.

Which sentence combines these two sentences with an appositive phrase?

Henry Ford adapted the assembly line, an innovation in factory production, to produce cars.

Henry Ford adapted the assembly line to make cars, and the assembly line is an innovation in factory production.

Adapting an innovation in factory production, Henry Ford used the assembly line to make cars.

Henry Ford adapted the assembly line, which was an innovation in factory production.