The correct answer is option 'B' - Madras to Northern Andhra Pradesh.

The Coromandel coast, located in the southern part of India, was an important cluster of weaving centers. The coast stretches from Madras (now Chennai) to Northern Andhra Pradesh. Let's explore this region in more detail:

1. Significance of the Coromandel coast:
- The Coromandel coast played a crucial role in the textile industry of India.
- It was known for its flourishing weaving centers that produced high-quality textiles.
- The region had a rich tradition of handloom weaving, with skilled artisans and weavers practicing their craft for generations.

2. Madras (Chennai):
- Madras, the capital city of Tamil Nadu, was a major center for weaving on the Coromandel coast.
- The city had numerous weaving clusters where various types of textiles were produced.
- Madras cotton, a lightweight and durable fabric, was highly valued and exported to different parts of the world.

3. Northern Andhra Pradesh:
- Moving northwards from Madras, the Coromandel coast extends to the region of Northern Andhra Pradesh.
- This area was also known for its weaving centers, contributing significantly to the textile industry.
- The region produced a wide range of textiles, including sarees, dhotis, and other traditional garments.

4. Weaving clusters:
- The weaving centers along the Coromandel coast were characterized by clusters of artisans and weavers working together.
- These clusters fostered a sense of community and facilitated the exchange of knowledge and techniques.
- Each cluster specialized in specific types of textiles, showcasing the diversity and expertise of the region.

5. Tradition and heritage:
- The weaving centers on the Coromandel coast have a long-standing tradition and heritage.
- The artisans and weavers in this region have preserved age-old techniques and designs, passing them down through generations.
- The textiles produced on the Coromandel coast are renowned for their intricate patterns, vibrant colors, and superior craftsmanship.

In conclusion, the important cluster of weaving centers on the Coromandel coast existed from Madras to Northern Andhra Pradesh. This region played a significant role in India's textile industry, producing a wide range of high-quality textiles and preserving a rich tradition of handloom weaving.