The correct answer is C. Western Disturbances.
Western Disturbances are extratropical storms that form over the Mediterranean Sea and move eastwards towards the Indian subcontinent. They are the main source of winter rainfall in the northwestern parts of the country, including Jammu.
Cyclones are tropical cyclones that form over the Bay of Bengal or the Arabian Sea. They are not a major source of rainfall in Jammu, as they usually track further south.
The South-West Monsoon is a seasonal wind that blows from the Indian Ocean to the Indian subcontinent. It is the main source of rainfall in the country, but it does not reach Jammu in winter.
The North-East Monsoon is a seasonal wind that blows from the Indian subcontinent to the Bay of Bengal. It is a weak monsoon that does not reach Jammu.
In conclusion, Western Disturbances are the main source of winter rainfall in Jammu.