<prompt> Pen test is done for elliciting which nerve injury -Median nerveUlnar nerveRadial nerveAxillary nerve  <response>: Pen test is used to test abductor pollicis brevis supply by median nerve action - abduction of the thumb pen test - the patient is asked to lay his hand flat on the table with palm facing the ceiling .A pen is held above the thumb the patient is asked to touch the pen with tip of the thumb .It will not possible in case of median nerve injury . REF:Essential ohopedics ,Maheshwari, 5th edition ,pg.no.66 