Which of the following conditions are necessary for the issue of a writ of 'Quo Warranto'?

(a) The office must be public and must be created by a statute or by the Constitution itself.

(b) The office must be substantive and not merely the function or employment of the servant at the will and during the pleasure of another.

(c) There has been a contravention of the Constitution or a statutory instrument in appointing such a person to the office.