In deciding whether there is a fire in your classroom building, which of the following provides the best early information as to whether there is a fire?

In deciding whether there is a fire in your classroom building, which of the following provides the best early information as to whether there is a fire?




A) the appearance of greenish flames
B) the appearance of a fireman in your classroom
C) the flicker of flames
D) the smell of smoke
E) the sound of an alarm bell


Answer: D