u will get brainliest

The baseball game went into extra innings. We had to stay at the park three extra hours.

Which sentence correctly joins these two simple sentences into a compound sentence?

A. The baseball game went into extra innings so we had to stay at the park three extra hours.
B. Because the baseball game went into extra innings we had to stay at the park three extra hours.
C. The baseball game went into extra innings we had to stay at the park three extra hours.
D. The baseball game went into extra innings, so we had to stay at the park three extra hours.