Which sentence is the correctly written compound sentence? A. The Battle of Gettysburg was fought in Pennsylvania on the first three days of July in 1863. B. On the first three days of July in 1863, the Battle of Gettysburg was fought in Pennsylvania. C. The Battle of Gettysburg was fought in Pennsylvania; it took place on the first three days of July in 1863. D. The Battle of Gettysburg was fought in Pennsylvania, it took place on the first three days of July in 1863.