Question

very aware, though, that a cave is more than just a hole in the ground. (10) as i entered the cave, i felt as if i was walking into a place totally disconnected from the land above, but dr. newman explained that an important relationship exists between the world above and the ground below. (11) he told us the water that created the cave runs into an underground reservoir that serves as the source of our drinking water, so the cave must be protected. (12) as our tour continued, dr. newman reminded us not to disturb or be damaging to the cave environment. (13) we learned that the farmer who owns the land takes special care to leave the ground around the cave undisturbed, even putting a gate across its entrance. (14) without this protection trash or other pollutants could enter the local water supply. (15) scientists have used nontoxic dye to trace how pollution travels through caves and into our water. (16) in truth, caves are vital components of the ecosystem of the surrounding area. (17) for example, we saw thousands of bats, including some endangered virginia big - eared bats. (18) they spend their days hanging upside down from the roof of the cave, but at dusk they fly out to eat insects. (19) most of the cave creatures, from the bats to the albino fish in the streams and the insects living under the rocks, obtain their food from the world above. (20) these cave directions: click and drag the comma into the correct location within the sentence. there may be one or more correct locations. (14) without this protection trash or other pollutants could enter the local water supply. correctly punctuate this sentence. without this protection trash or other pollutants could enter the local water supply.

Explanation:

A comma is needed after "protection" to separate the introductory prepositional phrase "Without this protection" from the main clause.

Answer:

Without this protection, trash or other pollutants could enter the local water supply.