在△ABC和△A′B′C′中，如果AB=9，BC=8，AC=5，A′B′=$\frac{9}{2}$ , B′C′=$\frac{5}{2}$，A′C′=4，那么 （    ）

把一个图形先沿着一条直线进行轴对称变换，再沿着与这条直线平行的方向平移，我们把这样的图形变换叫做滑动对称变换．在自然界和日常生活中，大量地存在这种图形变换（如图1）．结合轴对称变换和平移变换的有关性质，你认为在滑动对称变换过程中，两个对应三角形（如图2）的对应点所具有的性质是（    ）

根据短文内容, 判断句子正误。

Meeting Old Friends

    Tansey is an English girl. Her father and grandfather both love animals, so there are many animals on her grandfather's farm. When Tansey was young, she often played with animals. Two gorillas (大猩猩) are her best friends. Now look at the picture on the right! The little girl in the picture is Tansey. She was 18 months old then. The gorilla looked after her very well.

    In 2002, the two gorillas left Tansey and began to live in a forest. After twelve years, Tansey and her father came to the forest. Tansey called her best friends' names. Soon they met again. They hugged (拥抱)each other warmly (热情地). How lovely the two gorillas are！They are so friendly.

寒冷环境中，对人体的产热过程有直接促进作用的激素(     )