题目选项分析

Unlike Mesopotamian cities, in which buildings were arranged haphazardly, the cities of the Indus Valley all followed the same basic plan: houses were laid out on a north-south, east-west grid, and houses and walls were built of standard-size bricks.

Unlike the buildings in Mesopotamian cities, which were haphazard in arrangement, the same basic plan was used in all cities of the Indus Valley: houses were laid out on a north-south, east-west grid, and houses and walls were built of standard-size bricks.