The correct answer is:
B. During Beethoven's fourth period, he wrote atonal music that was often dissonant and unpleasing to the ear
Ludwig van Beethoven´s composing career has been divided into three: early, middle, and late period. The early period is considered to have last until 1802. The middle period lasted from 1802 to 1812, and the late period, the third, from 1812 to Beethoven´s death in 1827. There is no fourth period.