Final answer:
Macbeth's consideration of killing King Duncan is a violation of both ethical and political social contracts, disregarding the moral code and political obligations of loyalty and hospitality inherent in their feudal society.
Step-by-step explanation:
Macbeth would be violating both ethical and political contracts by killing Duncan. The correct answer is (c) Ethical and political contracts.
The concept of social contracts is key to understanding the ethical and political implications of Macbeth's contemplated actions. Killing King Duncan would constitute a breach of the underlying moral obligations that Macbeth has as a member of his society and as a subject of the king. An ethical contract dictates the moral code by which individuals must abide to maintain the trust and functionality within a society. Macbeth's contemplated regicide would disrupt the societal expectation that individuals will not commit harm against one another, particularly against a divinely anointed king.
Simultaneously, there is a political contract that arises from Macbeth's relationship with Duncan, who is not only his king but also a guest in his home, thus compounding the treachery with hospitality laws of the time. As a thane, Macbeth owes loyalty to his monarch, which is a political obligation embedded within the feudal hierarchy. The ethical and political social contracts together form the basis for Macbeth's societal duties, which he contemplates breaching for personal gain.