This question has been dealt with many times on Hubpages.
The reason is that these 2 countries have had a history of creating hacks that intentionally disrupt online activity. Google unfortunately paints all citizens from China and India with the same brush.
Even if you do gain approval, you have to prove that you're providing real value to internet users, and casting a wide social net as well. Even at that, Google can, and frequently does close accounts, seemingly on a whim or the flimsiest excuse.
Besides, Adsense is generally not worth it, in my experience. Unless you have a huge number of page views (and the type of content that advertisers pay a lot for), you'll be lucky to make more than a few pennies a week.