The correct answer is (a) New Delhi.
The National Bureau of Plant Genetic Resources (NBPGR) is an institute of the Indian Council of Agricultural Research (ICAR) located in New Delhi, India. It was established in 1966 with the objective of collecting, conserving, evaluating, and documenting plant genetic resources. The NBPGR has a collection of over 500,000 accessions of plant germplasm from all over the world. It also has a network of regional stations located in different parts of India. The NBPGR is involved in various activities related to plant genetic resources, such as germplasm collection, conservation, evaluation, documentation, and utilization. It also provides training and consultancy services in the field of plant genetic resources.
The other options are incorrect because:
(b) Kolkata is the capital of West Bengal.
(c) Mumbai is the capital of Maharashtra.
(d) Chennai is the capital of Tamil Nadu.