Using Black Scholes Formula ( Indian Context), how do I solve the below problem?

Look at secondary sources of data available on net, and asses Yes Bank as a option in the hands of its equity investors. Specifically look for the market value of Yes Bank when it was in stress. The book value and reason it as a real option for its investors assume that the option has a life of one year and the risk free rate of interest is 5%. (make assumptions only in case you feel a desperate need to do so!!)