Final answer:
The extensor carpi radialis, extensor digitorum, and extensor carpi ulnaris muscles are homologous to each other in the upper and lower limbs. They are innervated by the radial nerve in the upper limb and the posterior tibial nerve in the lower limb.
Step-by-step explanation:
The muscles that are homologous to each other in the upper and lower limbs are the extensor carpi radialis, extensor digitorum, and extensor carpi ulnaris. These muscles are responsible for extending the wrist and fingers.
The nerve supply for these muscles in the upper limb is the radial nerve, and in the lower limb, it is the posterior tibial nerve. The radial nerve innervates the extensor muscles in the posterior compartment of the forearm, while the posterior tibial nerve innervates the muscles in the posterior leg.