The correct answer is A. Naked.
A shameful act is one that is considered to be morally wrong or reprehensible. The opposite of shameful is something that is considered to be morally right or praiseworthy.
Naked is not the opposite of shameful. Naked simply means not wearing any clothes. It is not necessarily a shameful thing to be naked, although it may be considered to be inappropriate in some situations.
Brazen is not the opposite of shameful. Brazen means bold or impudent, especially in a way that is offensive or insulting. It is not necessarily a shameful thing to be brazen, although it may be considered to be rude or disrespectful in some situations.
Wanton is not the opposite of shameful. Wanton means unrestrained or uncontrolled, especially in a way that is morally reckless or depraved. It is not necessarily a shameful thing to be wanton, although it may be considered to be immoral or irresponsible in some situations.
Unblushing is not the opposite of shameful. Unblushing means not showing any shame or embarrassment. It is not necessarily a shameful thing to be unblushing, although it may be considered to be arrogant or insensitive in some situations.
In conclusion, the opposite of shameful is something that is considered to be morally right or praiseworthy. Naked, brazen, wanton, and unblushing are not necessarily the opposite of shameful.