Hey there!
The correct answer to your question is option "D." abaaca
Here is why:
That conqueredst Alexandria by the right (A)
Of arms, and didest woe on heathens too, (B)
The very liegmen envied thee, and spite (A)
(No other cause) against thy chivalrous might (A)
Moved them to murder thee upon the morrow (C)
There, on thy bed! Thus Fortune with light (A)
The first line ends with "right", so the next scheme that has the letter "A" is going to have to rhyme with the word "right". The next line is "B" because "too" does not rhyme with the word "right" and so on.
Hope this helps you.
Have a great day!