Read the following statements.

(a) In the last 27 years, there has been disappearance of 20 species.
(b) Bali, Java and Caspian tigers are included in recently extinct animals.
(c) If we apply May's estimate, then there are probably more than 1,00,000 plant species in India that are yet to be discovered and described.
(d) There is more solar energy available in the tropics, which contributes to higher productivity.

Select the correct option.