Correct option is B
Solan in Himachal Pradesh is known as the Mushroom City of India.
It houses the Directorate of Mushroom Research (DMR), India’s premier mushroom institute.
Modern cultivation methods were first popularized here.
Solan leads in spawn production and training facilities.
Many national-level mushroom programmes are conducted in this region.
Hence, Solan earned the title due to its major contribution to mushroom development in India.