In the Middle Ages, most people lived in villages and worked as agricultural laborers, or peasants. Every village had a “lord,” and peasants worked on his land. Much of what they produced went to the lord and his family. What little food was leftover went to support the peasants’ families. In return for their labor, the lord offered them protection. A peasant’s day usually began before sunrise and involved long hours of backbreaking work, which included plowing the land, planting seeds, and cutting the crops for harvesting. The working life of a peasant in the Middle Ages was usually demanded and exhausting.
D. is wrong. It should be "One hero in the animation field is Mel Blanc, the voice behind many cartoon characters." because the information after Mel Blanc is not necessary to the sentence. It's just extra, so you need a comma.
i believe the answer is d
