The answers are A and C.
The Indus Valley Civilization had an amazing system of plumbing which still stuns historians. In Europe, they didn't know plumbing until 18th century.
Also, they were one of the first civilizations on Earth who developed a standardized system of measurements. It was very hard back then, when people doesn't have that accurate tools made from proper materials.
The stepped pyramids were more of a feature of Mesoamerican civilizations.
Also the embalming of the dead was a tradition of Egyptians.
