材料一：自从我担任目前职务以来，我的主要任务就是为欧洲的绥靖……捷克斯洛伐克问题是最后的，说不定还是一个最危险的问题。既然我们已经走过来了，我觉得可以沿着这条通向稳定的道路继续前进了。

——1938年10月3日张伯伦在英国下院的辩论词
材料二：我们的目的是什么？我可以用一个词来回答：胜利----不惜一切代价去争取胜利，无论多么恐怖也要争取胜利：因为没有胜利，就不能生存。      ——1940年5月丘吉尔在英国下院的演讲

已知两不共线向量$\overrightarrow{a}=\left(\cos \alpha ,\sin \alpha \right),\overrightarrow{b}=\left(\cos \beta ,\sin \beta \right)$,则下列说法不正确的是 （　　）

    In northern Scotland there is a long deep lake called Loch Ness.  More than 200 meters deep, it is the largest lake in the UK.  People  say  a  big monster (怪兽)  lives in its dark, cold waters. It weighs more than 1,000 kilos and is at least ten meters long. Some people say it has a head like a horse. Others say it looks like a snake. Many people travel to Loch Ness to look for this strange monster, but only a few people have seen it. At least, they say they have seen it.

    The Loch Ness Monster is a famous legend (传说). The first story about a monster in Loch Ness was told over 500 years ago, but the legend of the monster spread widely only in the twentieth century. In 1933, a husband and wife reported that they saw a big monster in Loch Ness. Several people have taken photos, but at least one of them was a hoax (骗局). During the 1960s, a team was formed to look for the monster. They took many photos and made movies, but they were never able to find a monster.

    There is no real fact that a monster lives in Loch Ness, but there is also no fact that one doesn't live. One thing is true about Loch Ness: there are a lot of tourists there.