Explanation:

The correct answer is option 'D' - Anga.

During the period mentioned in the question, several big cities emerged as political and administrative centers in different regions of the Indian subcontinent. Let's discuss each option to understand why 'Anga' is not the capital of any big city during that period.

a) Pawa:
Pawa, also known as Pataliputra, was the capital city of the Magadha kingdom. It was one of the largest and most prosperous cities of ancient India. Pataliputra was strategically located on the banks of the Ganges River and served as a political and economic hub. It was the capital of several powerful dynasties, including the Mauryas and the Guptas. The city was known for its grandeur, with palaces, temples, and other impressive structures.

b) Champa:
Champa, also known as Bhagalpur, was an important city in the Anga region of ancient India. It was the capital of the Anga kingdom, which was one of the Mahajanapadas (great kingdoms) during that time. Champa was known for its skilled craftsmen and traders. It played a significant role in the economy and trade of the region.

c) Rajgriha:
Rajgriha, also known as Rajgir, was the capital city of the Magadha kingdom before Pataliputra. It was an important political and cultural center during the period mentioned in the question. Rajgriha is famous for being the place where Lord Buddha spent a considerable amount of time and delivered many important teachings. The city had several monasteries and was a popular destination for pilgrims.

d) Anga:
Anga was not the capital of any big city during the period mentioned in the question. It was an ancient kingdom located in the eastern part of the Indian subcontinent, corresponding to present-day Bihar and parts of Jharkhand. The capital of the Anga kingdom is not well-documented, and there is no evidence to suggest that it had a prominent city as its capital during the specified period.

In conclusion, among the options mentioned, 'Anga' is not the capital of any big city during the mentioned period. The other options, Pawa (Pataliputra), Champa (Bhagalpur), and Rajgriha (Rajgir), were all significant cities in ancient India.