The correct answer is D. Twelfth Amendment Act of Jammu and Kashmir, 1975.
The First Amendment Act of Jammu and Kashmir, 1959, was enacted to provide for the appointment of a Chief Justice of the Jammu and Kashmir High Court. The Fifth Amendment Act of Jammu and Kashmir, 1962, was enacted to provide for the appointment of a Governor of Jammu and Kashmir. The Sixth Amendment Act of Jammu and Kashmir, 1965, was enacted to provide for the appointment of a Chief Minister of Jammu and Kashmir.
The Twelfth Amendment Act of Jammu and Kashmir, 1975, was enacted to provide for the appointment of a Prime Minister of Jammu and Kashmir. However, this amendment was never implemented. The reason for this is that the Constitution of Jammu and Kashmir was amended in 1974 to provide for the office of a Chief Minister instead of a Prime Minister. Therefore, the Twelfth Amendment Act of Jammu and Kashmir, 1975, is not a valid law.