一项最新研究结果表明，含有有毒气体的厌氧海水间歇性上涌，造成生物物种的大量减少及灭亡。这一发现不仅丰富了人们对地球生命灭绝的认识，而且对研究现代全球气候变化具有重要启示：大气中二氧化碳的不断升高可能导致海洋缺氧，对人类生存环境造成很大破坏。上述研究结果及启示表明（ ）
①认识具有无限性，在实践基础上不断深化发展
②实践具有历史性，其内容和水平不断丰富和提高
③联系具有普遍性，人与自然相互影响和相互作用
④矛盾具有同一性，双方在一定条件下可以相互转化

阅读下面短文, 从每题所给的A、B、C、D四个选项中选出最佳选项。

D

    How old is "old"? The answer has changed over the years. Two Hundred years ago, you were old at 35. At the beginning of the 20th century, the average life span(平均寿命) was 45. In 1950, 70-year-olds were really old. Today, a healthy 70-year-old is still thought young.

    So, how old is "old"? The answer is one you've heard many times, from all kinds of people. "You are as old (or young) as you feel. " Your age simply tells you how many years you have lived. Your body tells you how well you've lived.

    "Nobody grows old by living a number of years, "Wrote a writer. "People grow old when they don't have their ideals(理想)." People shouldn't have the wrong ideas about aging. Sometimes, older minds can be as bright as young minds. Alice Brophy once said, "It makes me unhappy when people say, 'You look young for your age.' What does that mean? You know you can die old at 30 and live young at 80."

下列表述不属于北魏孝文帝改革客观背景的是

在学习“第一次燃遍全球的战火”的历史课上，有些同学认为德国是有罪的，而有些同学则主要责备英国和法国，还有些同学说这罪行双方都有份，总的说来，第一次世界大战的性质应该是（　　）

看图填空。