在探究骨的成分和特性的实验中,把鱼骨浸泡在稀盐酸中,实验后会变成
A:变轻、变软
B:变轻、变硬
C:变重、变硬
D:变重、变软
Every year,because of the destruction of man,many of the earth's plants and animals are________.
一条神经是指( )