Explanation:

- Statement I: SEBI is actually not the regulator of commodity markets; the Forward Markets Commission (FMC) was the regulator before SEBI took over in 2015. However, SEBI primarily focuses on the securities market.

- Statement II: RBI is indeed the regulator of Non-Banking Financial Companies (NBFCs), overseeing their operation to ensure financial stability.

- Statement III: SEBI is the regulator of the capital market in India, ensuring protection for investors and developing and regulating the securities market.

Now, examining the options:

- Option 1: Only I - Incorrect, because Statement I is not entirely correct.

- Option 2: I and III only - Incorrect, Statement I is not correct.

- Option 3: I, II and III - Incorrect, Statement I is not correct as explained.

- Option 4: II and III only - Correct, both statements are true!

- Option 5: None of the above - Incorrect, as there is a correct combination.

Answer: Option 4 - II and III only.