下列物质的用途，主要体现该物质的物理性质的是( )

A．点燃熄灭蜡烛火

B．氢气制盐酸

C．活性炭净水

D．氢氧化钠制叶脉书签

In a Natural Approach class, which of the following is NOT an acquisition activity

A. Affective-humanistic activity.

B. Problem-solving activity.
C. Content activity.


D. Translation activity.