While criticizing the arguments that appeal to the unnaturalness of homosexuality to show it is wrong. Corvino argues that a. it is false to claim that all nonreproductive sex is wrong b. if "natural" means "usual", then it is morally irrelevant to say homosexuality is unnatural c. even if the primary purpose of sex is procreation, it does not follow to that it is bad to use sex solely for pleasure d. all of the above A hypothetical imperative cannot be the basis of moral duty, according to Kant, because a. its force depends on whether the agent wants to attain a particular goal b. it ignores self-interest c. it accepts reasons without regard to feelings The Difference Principle claims that inequalities are arbitrary and unjust, unless a. the positions and offices to which they attach are open to all b. they improve the chances for security, wealth and happiness for most c. they work out to everyone's advantage d. both b and c e. both a and b f. both a and c