The correct sequence of sound waves in the ear is
select one:
a. stapes > eardrum > malleus > oval window
b. auditory tube > incus > malleus > stapes > eardrum
c. eardrum > stapes > incus > malleus > inner ear
d. malleus > incus > stapes > oval window

d. malleus > incus > stapes > oval window

Explanation:

Sound waves enter external auditory canal which makes the eardrum to vibrate. Malleus is in contact with eardrum while stapes is in contact with the oval window. Movement of malleus makes the incus to move which in turn stimulates large movement in stapes.  

Since stapes is in contact with the oval window, the vibration from stapes passes to the oval window. Hence, among the given options, the correct order of movement of sound waves is "malleus > incus > stapes > oval window" .

you know they are heterozygous for a trait because they have it as jj or jj.