Article 263 provides for the establishment of an Inter-State Council to effect co-ordination between States. Consider the following in relation to its functions and answer through the below given codes :

a. Inquiring into and advising upon disputes which may arise between States.

b. Investigating and discussing subjects in which some or all of the States of the Union and one or more of States have common interest.

c. Making recommendation on any subject and for the better co-ordination of the policy and action with respect to that subject.

d. The rulings of the Council shall be mandatory to all States.