Step 1: Scope of Section 6, Specific Relief Act.
Section 6 provides a summary remedy to restore possession to a person who has been dispossessed otherwise than in due course of law.
Step 2: Nature of dispossession.
The remedy is available only when dispossession is without the consent of the person and not pursuant to lawful authority.
Step 3: Conclusion.
Therefore, the correct answer is (A) without their consent.