<prompt> Median nerve injury at the wrist is commonly tested by-Contraction of abductor pollicis brevisContraction flexor pollicis brevisLoss of sensation on palmLoss of sensation on ring finger  <response>: Abductor pollicis brevis and flexor pollicis brevis, both are supplied by the median nerve. However, flexor pollicis brevis cannot be tested separately because flexion of metacarpophalangeal joint of the thumb the function of flexor pollicis brevis can also be produced by flexor pollicis longus. On the other hand abductor pollicis brevis can be tested separately.Option c d are incorrect in regards to this question. Though, sensory loss over palm lateral 23 and ring finger lateral half occurs in median nerve injtuy, these area are not used to test sensory loss. For testing, the sensory deficit in median nerve injury tip of the index and middle finger autonomous zone are used. 