The sequence of the one-way gaseous exchange mechanism in a fish is?

A. gills ⇢ operculum ⇢ mouth
B. mouth ⇢ gills ⇢ operculum
C. mouth ⇢ operculum ⇢ gills
D. operculum ⇢ mouth ⇢ gills

Correct Answer:

Option B – mouth ⇢ gills ⇢ operculum