The correct answer is option 3, Indian Forest Service. The Indian Forest Service is one of the All India Services established by the Government of India. The All India Services are elite civil services of the Indian government and are constituted by three services - the Indian Administrative Service, the Indian Police Service, and the Indian Forest Service.

Option 1, Indian Audit and Accounts Service, is not categorised as an All India Service. It is a central civil service that is responsible for auditing the accounts of the central and state governments.

Option 2, Indian Railway Service, is also not categorised as an All India Service. It refers to various services within the Indian Railways, such as the Indian Railway Traffic Service, Indian Railway Accounts Service, Indian Railway Personnel Service, etc.

Option 4, Indian Economic Service, is also not categorised as an All India Service. It is a Group A service of the Indian government that deals with economic analysis, policy formulation, and research.

Therefore, the correct answer is indeed option 3, Indian Forest Service.