We can safely say that India would be in a better state had it not been for the ____________ politicians who are ______________ with matters of public ________________. 

Let us discuss all options. In option B, ‘corrupt’ can be a possible answer but ‘bothered’ and ‘distress’ are out of context. In option C, ‘diligent’ does not make the sentence meaningful even though ‘disconnected’ can be correct. In option D, ‘meticulous’ is incorrect as it is out of context with what the sentence is saying even though ‘anxious’ may be a possible answer. All three words of option A make the sentence meaningful and complete. The correct sentence is - We can safely say that India would be in a better state had it not been for the scrupulous politicians who are unconcerned with matters of public welfare.