Let's think of it like this. We have an energy crisis, but how can we solve it? There are three steps. First, we need to recognize that we HAVE a problem that needs to be fixed. Then, we need to determine what's causing the problem. Finally, we need to change how we act in order to solve the problem. Now, let's look at the options.
Is A correct, leaving our behavior unchanged? NO: if we know the cause of the problem, we still need to solve it! What about B: the problems are ignored? NO: you can't solve a problem unless you know it's a problem. C? NO: to solve a problem, you need to find out what's causing it. Finally, let's look at D: behavior is changed after cause is identified. This is correct: not only do we know why it's happening, but we're fixing it!
Answer: D
