Which one of the following statements about the All India Services is correct?

1. AThe All India Services may be created by an Act of the Parliament.
2. BThe endorsement of the Rajya Sabha is not essential for the creation of the All India Services.
3. CThe rules of recruitment to the All India Services are determined by the UPSC.
4. DThe conditions of service to the All India Services may be altered by the UPSC.