呵呵，这个问题其实是不需要答案的，用中国人的话说，就叫：寒暄。 通常，中国人会回答：还好！

I agree with the answers above. Still something to add. 不太好 马马虎虎 很好 非常好 挺好 The possible anwers you listed are all possible. However, personally, I would use 挺好的, 你呢 as a reply. Because 很好/非常好 sounds a little bit "over-excited" to my ears, while 不太好 sounds a bit down. As you can see from the answers, we tend to use answers implying moderate level of "being good". However, to close friends, I will express 不太好 to them, if I really feel bad. As for 好啊/很好啊, I think 很好啊 can be a better choice if I need to choose between the two. Because 好啊 more sounds like "Yes"--the reply you would give to questions like "Would you like to do sth."(做某事行吗) instead of "你好吗". Still, personally I won't use them neither. I would say 挺好的啊, if I want to add “啊” after it. Adding 啊 makes it sound very casual and conversational.

还行吧，将就着，还可以，恩 不错，一般般，不爽啊，等等太多了

+ 不错

Chinese people prefer "你最近怎么样？" to "你好吗？" for greeting. 你好吗 is not common in China. Chinese people like to use "你吃饭了吗？"，because China is an agricultural country and they always care about subsistence problem.