The correct answer is A. Poverty : Wealth.
Joy and euphoria are both positive emotions, while poverty and wealth are both economic states. Melancholy and depression are both negative emotions, while sorrow and joy are opposite emotions. Noise and pollution are both environmental factors that can be harmful to human health.
In the original pair of words, joy is a more intense form of happiness. Similarly, wealth is a more extreme form of prosperity. In the other options, the second word is not a more intense form of the first word. For example, poverty is not a more extreme form of lack of money, and sorrow is not a more intense form of sadness.