The correct answer is: a) Jorhat.
Jorhat is a city in the Indian state of Assam. It is the headquarters of Jorhat district and the North Eastern Frontier Railway zone. The city is located on the banks of the Brahmaputra River, about 250 kilometers (160 mi) east of Guwahati.
Jorhat is known as the “Tea Capital of India” because it is the largest producer of tea in the country. The city is home to several tea gardens, including the oldest tea garden in India, the Jorhat Tea Estate.
Jorhat is also a major educational center in Assam. The city is home to the Jorhat University, the Assam Agricultural University, and the Assam Engineering College.
In addition to tea, Jorhat is also known for its silk industry. The city is home to several silk mills, which produce a variety of silk products, including sarees, scarves, and shawls.
Jorhat is a popular tourist destination. The city is home to several historical monuments, including the Jorhat Fort, the Ahom Palace, and the Sibsagar Palace.
The other options are incorrect because they are not the headquarters of Jorhat district. Dibrugarh is the headquarters of Dibrugarh district, Tinsukia is the headquarters of Tinsukia district, and Sonitpur is the headquarters of Sonitpur district.