In which of the following regions of India are shale gas resources found? 1. Cambay Basin 2. Cauvery Basin 3. Krishna-Godavari Basin Select the correct answer using the code given below.

1. (a)1 and 2 only
2. (b)3 only
3. (c)2 and 3 only
4. (d)1, 2 and 3