What do the words hydrant, hydroplane, hydrology, and hydrotropic have in common?

A) a root word

B) a suffix

C) a free morpheme

D) a base word

A) a root word

C) a free morpheme

And they also have in common that if you say each word five times really fast, you'll sound like a splashing water balloon. Go ahead, give it a try!

The words hydrant, hydroplane, hydrology, and hydrotropic have the root word "hydro-" in common. Therefore, the answer is A) a root word.

The words hydrant, hydroplane, hydrology, and hydrotropic all have the root word "hydro" in common. The root word "hydro" comes from the Greek word "hydor," which means water.