甲基硫菌灵危险特性是什么？
参考答案：遇火星会发生爆炸。遇明火、高热可燃。其粉体与空气可形成爆炸性混合物，气体。
A turning point of the continuously high housing price won't appear suddenly because there must be
a certain process ________ many factors lead to the change.[ ]
A. which
B. what
C. where
D. that
试述垫的形成原因。
