Which bits of an IPv4 multicast address are mapped to bits of a MAC address?

A.
lower 23 of IPv4 to lower 23 of the MAC address

B.
upper 23 of IPv4 to upper 23 the MAC address

C.
upper 23 of IPv4 to lower 23 the MAC address

D.
lower 23 of IPv4 to upper 23 the MAC address