Which type of fuel is difficult to extinguish using water as the only extinguishing agent?

Select one:

a. Liquids that are less dense (lighter) than water

b. Liquids that are more dense (heavier) than water

c. Miscible liquids

d. Polar solvents

Option A

Explanation:

Fighting flammable substances such as grease or oils fires with water is dangerous and might cause it to spread as the liquids are less dense than water and hence forms a layer on top of water. Water will thus increase the surface area for the less dense liquids to spread, hence spreading the fire.