The correct order of coal mines from north to south is as follows:
- Singrauli (III): Located in Madhya Pradesh and Uttar Pradesh, it is in the northernmost position.
- Korba (IV): Located in Chhattisgarh, south of Singrauli.
- Singareni (I): Located in Telangana, further south of Korba.
- Neyveli (II): Located in Tamil Nadu, which is the southernmost coal mine in this list. Thus, the correct option is (C).