Odd man out of the following options. One among them is not related to other three.

In the given options, BIS is the odd one from the other three.  NABARD, RBI & IRDA are the bodies related to financial sector of India. The financial sector consists of banks, investment funds, insurance companies and real estate firms. 

BIS stands for Beareau of Indian Standards is a National standard body of India with the activities of standardization, marking and quality certification of goods.