This is a question with answer options. Goal: How to lock a door from the inside

Which of the following methods is more reasonable for accomplishing this goal?

Available choices: [-] Close the door. Turn the knob on the lock in the appropriate direction to lock it. Test the door by twisting the knob and see if it opens.; [-] Open the door the door. Turn the knob on the lock in the appropriate direction to lock it. Test the door by twisting the knob and see if it closes.;...I think the answer is
Close the door. Turn the knob on the lock in the appropriate direction to lock it. Test the door by twisting the knob and see if it opens.