Which mortgage must be registered even if the principal money secured in less than Rs. 100

Disputes between States in India can be heard by the Supreme Court under

A contract for the sale of immovable property under the Transfer of Property Act

Optional registration of lease of immovable property under the Transfer of Property Act is

A lease of immovable property which can be made only by registered instrument under the Transfer of Property Act is

After which one of the following case, Supreme Court decision relating to the special provisions socially & educationally backward classes was introduced by an amendment of the Constitution