The correct answer is: B. Rs 40.00
The expected final stock price is the original investment plus the expected capital gain. In this case, the original investment is Rs 30 and the expected capital gain is Rs 10, so the expected final stock price is Rs 30 + Rs 10 = Rs 40.
Option A is incorrect because it is the expected capital gain, not the expected final stock price.
Option C is incorrect because it is the negative of the expected final stock price.
Option D is incorrect because it is the negative of the expected capital gain.