下列几种变异中，不能遗传的变异是（ ）
A．人类的皮肤的白化
B．玉米粒的黄白
C．人的色盲
D．生长在遮阴处的小麦杆细穗小
答案：D
题目分析：可遗传的变异是由遗传物质改变引起的，可以遗传给后代，由环境改变引起的变异，是不遗传的变异，不能遗传给后代，生长在遮阴处的小麦杆细穗小，是环境条件改变引起的变异，遗传物质没有发生改变，是不遗传的变异，不能遗传给后代，人类的皮肤的白化、玉米粒的黄白红、人的色盲，是由于遗传物质改变引起的变异，可以遗传给后代，属于可遗传的变异，所以此题答案为D。
点评：此题为基础题，较易，解答此类题目的关键是理解变异的原因。
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| Around twenty years ago I was living in York. 1 I had a lot of experience and a Master's degree, I could not find 2 work. I was 3 a school bus to make ends meet and 4 with a friend of mine, for I had lost my flat. I had 5 five interviews (面试) with a company and one day between bus runs they called to say I did not 6 the job. "Why has my life become so 7 ?" I thought painfully. As I pulled the bus over to 8 a little girl, she handed me an earning 9 I should keep it 10 somebody claimed (认领) it. The earring was painted black and said "BE HAPPY". At first I got angry. Then it 11 me - I had been giving all of my 12 to what was going wrong with my 13 rather than what was right! I decided then and there to make a 14 of fifty things I was happy with. Later, I decided to 15 more things to the list. That night there was a phone call for 16 from a lady who was a director at a larger 17 . She asked me if I would 18 a one-day lecture on stress (压力) management to 200 medical workers. I said yes. My 19 there went very well, and before long I got a well-paid job. To this day I know that it was because I changed my way of 20 that I completely changed my life. | ||||
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