Read the article and select the best answer. Article: In all one's lifetime it is oneself that one spends the most time being with or dealing with. But it is exactly oneself that one has the least understanding of. When you are going upwards in life you tend to overestimate yourself. It seems that everything you seek for is within your reach. When you are going downhill you tend to underestimate yourself, mistaking difficulties for your own incompetence. To get a thorough understanding of oneself is to gain a correct view of oneself-aware of both one's strengths and shortages. You may look forward hopefully to the future but be sure not to expect too much, for ideals can never be fully realized. You may be courageous to meet challenges but it should be clear to you where to direct your efforts. That's to say so long as you have a perfect knowledge of yourself there won't be difficulties you can't overcome. To get a thorough understanding of oneself needs self-appreciation. Whether you think you are a towering tree or a blade of grass, a high mountain or a small stone, you represent a state of nature that has its own value. If you earnestly admire yourself you'll have a real sense of self-appreciation, which will give you confidence. As soon as you gain full confidence in yourself, you'll be enabled to fight and overcome any adversity. To get a thorough understanding of oneself also requires doing oneself a favor when it's needed. In time of sadness, do yourself a favor by sharing it with your friends so as to change a gloomy mood into a cheerful one; in time of tiredness, do yourself a favor by getting a good sleep. As you are aware, what a person physically has is but a human body that's vulnerable when exposed to the elements. So if you fall ill, it's up to you to take a good care of yourself. In a word, to get a thorough understanding of oneself is to get a full control of one's life. Then one will find one's life full of color and flavor. Question: Remember not to expect too much of yourself when looking forward to the future because _ . Options: A: your shortages might stop you succeeding B: ideals can never be turned into realities C: you are likely to lack enough courage D: you haven't understood yourself quite well
A