So first make sure you know what the author’s conclusion is. It’s in the last paragraph: that the government should let people and their doctors make individualized meal plans for themselves.
So, C and D are out because they both support the government intervening.
A may or may not be true, but it doesn’t really answer the question. It doesn’t support the author’s conclusion—it’s just a statement about one aspect of the government’s actions.
B is really the only option that supports the author. He’s saying the government should butt out. Option B is saying that obesity rates were lower before the government got involved. That supports the government butting out because their involvement made things worse.