单项选择题

TEXT C
Taking charge of yourself involves putting to rest some very prevalent myths. At the top of the list is the notion that intelligence is measured by your ability to solve complex problems; to read, write and compute at certain levels; and to resolve abstract equations quickly. This vision of intelligence asserts formal education and bookish excellence as the true measures of self-fulfillment. It encourages a kind of intellectual prejudice that has brought with it some discouraging results. We have come to believe that someone who has more educational merit badges, who is very good at some form of school discipline is "intelligent." Yet mental hospitals are filled with patients who have all of the properly lettered certificates. A truer indicator of intelligence is an effective, happy life lived each day and each present moment of every day.
If you are happy, if you live each moment for everything it’s worth, then you are an intelligent person. Problem solving is a useful help to your happiness, but if you know that given your inability to resolve a particular concern you can still choose happiness for yourself, or at a mini mum refuse to choose unhappiness, then you are intelligent. You are intelligent because you have the ultimate weapon against the big N. B. D. Nervous Break Down.
"Intelligent’ people do not have N. B. D. ’s because they are in charge of themselves. They know how to choose happiness over depression, because they know how to deal with the problems of their lives.
You can begin to think of yourself as truly intelligent on the basis of how you choose to feel in the face of trying circumstances. The life struggles are pretty much the same for each of us. Every one who is involved with other human beings in any social context has similar difficulties. Disagreements, conflicts and compromises are a part of what it means to be human. Similarly, money, growing old, sickness, deaths, natural disasters and accidents are all events which present problems to virtually all human beings. But some people are able to make it, to avoid immobilizing depression and unhappiness despite such occurrences, while others collapse or have an N. B.D. Those who recognize problems as a human condition and don’ t measure happiness by an absence of problems are the most intelligent kind of humans we know; also, the roost rare.
According to the passage, what kind of people are rare