[单项选择]在y轴的截距为-3，且与直线2x+y+3=0垂直的直线方程是（）.
A. x-2y-6=0
B. 2x-y+3=0
C. x-2y+3=0
D. x+2y+6=0

In 1575--over 400 years ago the French scholar Louis Le Roy published a learned book in which he voiced despair over the changes caused by the social and technological innovations of his time, what we now call the Renaissance. We, also, feel that our times are out of joint; we even have reason to believe that our descendants will be worse off than we are.
The earth will soon be overcrowded and its resources exhausted. Pollution will ruin the environment, upset the climate and endanger human health. The gap in living standards between the rich and the poor will widen and lead the angry, hungry people of the world to acts of desperation including the use of nuclear weapons as blackmail. Such are the inevitable consequences of population and technological growth if present trends continue.
The future is never a projection of the past. Animals probably have no chance to escape from the tyranny of biological evolution, but human beings are blessed with the freedom of s
A. an assertion is made, followed by a few examples to illustrate it
B. future dangers are stated and relative measures are to be adopted
C. a historical trend is stated and evidence is then provided to prove it
D. examples of risks are given and reasons are then advanced to clarify them

材料一：19世纪晚期德国的幼儿园在F．W．A．福禄贝尔推动下有很大发展，各级各类学校数量不断增加。以普鲁士地区为例，1867—1881年间新建的学校达6000多所。而职业教育与实科学校教育的发展尤为突出，在世界上处于领先地位。
——摘编自马立志《成功的教育》
材料二：1912年1月19日，南京临时政府教育部颁布《普通教育暂行办法》。规定“初等小学可以男女同校”；“小学手工科，应加注重”；“开设的科目有修身、国文、外国语、历史、地理、数学、博物、物理、化学、法制、经济、图画、手工、乐歌、体操”；“初等小学算术科，自第三年起兼课珠算”；“中学校为普通教育，文、实不必分科”；“小学读经科一律废止”；“废止旧时奖励（科举）出身”的作法，一律称该类学校的毕业生；“凡各种教科书，务合乎共和民国宗旨，清学部颁行之教科书，一律禁用”。
——摘编自裘士京《中国文化史》
材料三：上世纪80年代以来，西方各国加快了课程改革的步伐。《美国2000年教育战略》提出，要开发有关自然科学学科的全国统一标准，将数学和自然科学列入5门核心课程（另外三门是英语、历史和地理）中。1986年，法国国民教育部公布高中课程改革计划，规定必修课设物理和自然科学。各国在课程的设置上，把人文科学放在同等重要的地位。特别是一些发达国家如日本、美国、原联邦德国和英国都把人文科学作为重要的课程内容。这其中，为了重建精神价值，恢复道德教育，各国都对道德价值观念和教育给予了极大的关注，越来越把道德价值观念结合进“课程设计”和“校外教育设计”之中。
——摘编自卜玉华《世界课程改革的发展趋势》