Answer:
D. Art not without ambition, but without / The illness should attend it.
Step-by-step explanation:
This evidence shows that Macbeth's isn't sufficiently remorseless to slaughter the king. He has a thoughtful heart and does not consider murdering the king due to his egotistical reasons worthy.
In contrast to him, Lady Macbeth is pitiless and she yearns for power so she would do anything, regardless of whether it implies killing somebody, to get what she needs.