Judicial review implies the right of the Court to :

declare any law or order invalid if it is in conflict with the.Constitution
review the order of the lower courts.
hear appeals against the decission of the lower courts.
review the laws to see that they have been passed as per the procedure laid down.

The correct answer is (a). Judicial review is the power of the courts to declare laws or government actions unconstitutional. It is a check on the power of the legislative and executive branches of government.

(b) is incorrect. The power to review the order of the lower courts is called appellate jurisdiction.

(c) is incorrect. The power to hear appeals against the decision of the lower courts is also called appellate jurisdiction.

(d) is incorrect. The power to review the laws to see that they have been passed as per the procedure laid down is called legislative oversight.