Separation of the Judiciary from the executive is enjoined by:

a) Preamble
b) Directive Principle
c) Seventh Schedule
d) Judicial Decision

Ans-b

Explanation Article 50 of the Indian constitution talks that the State shall take steps to separate the judiciary from the executive in the public services of the State. It is one of the liberal intellectual principle.

Preamble is the source of authority of constitution, defines nature of Indian state and specifies objectives of the constitution.

Seventh schedule defines distribution of powers between Union and states.