OPTION 2) i.e. MR. Puri ASKED me why I was taking down that fence.While changing DIRECT speech into indirect speech, interrogative sentences should be changed to assertive sentences.Option 1) cannot be the correct answer because a helping VERB has been used before the subject.In option 3) why and that are used simultaneously which is wrong.In option 4) said to is not changed into asked, so, it cannot be the correct answer.