The correct answer is option 1, the Indus Valley civilization. The Indus Valley civilization is considered one of the oldest known civilizations in India. It existed around 2500 BCE to 1900 BCE, in what is now present-day Pakistan and northwest India. The civilization thrived along the Indus River and is known for its advanced urban planning, sophisticated sewerage systems, and well-organized trade networks. The Indus Valley civilization is also known for its intricate craftsmanship and unique script that is still undeciphered today. The Mesopotamian civilization, mentioned in option 2, developed in the region of modern-day Iraq and Syria and is one of the oldest civilizations in the world but not the oldest in India. Similarly, option 3, Egyptian civilization, developed along the Nile River in Africa and is also one of the oldest civilizations, but not in India. Therefore, the correct answer is option 1.