Question

which nerve root causes medial arm sensory loss and hand intrinsic weakness? c6 c8 t1 c7

Explanation:

T1 nerve root innervates the medial arm for sensation and supplies the intrinsic hand muscles. Damage to T1 results in the described symptoms, while other roots affect different arm regions/muscles: C6 affects lateral arm, C7 affects posterior arm, C8 affects medial forearm.

Answer:

T1