Select the correct answer.
which statement best defines why sound waves are mechanical waves?
oa. they require a medium in which to travel.
ob. they can travel through vacuum.
oc. they can travel only through solids.
od. they can travel only through gases.

A. They require a medium to travel through

Explanation:

The medium can be any substance-solid,liquid,or gas- and the wave's speed depends on the properties of the material of the medium the wave travels through.

i wish i could with all of them i can barley see the first one so here's the answer to the first one b