Read each sentence to find out whether there is any grammatical mistake/error in it. The error if any, will be in one part of the sentence. Mark the letter of the part with error as your answer. If there is no error, mark (e) as your answer.
Today there are very few (a)/ tigers left in India (b)/ and many NGOs are ( c )/ working saving our national animal. (d)/ No error ( e ).

Explanation

(d) Replace .saving. by .to save.