Which detail from "Space Junk!" best conveys that the author is concerned that space junk will have a negative impact on our planet?

"Although space is extremely vast, most of the junk that is worrisome is orbiting earth."

"Currently, there are around 900,000 pieces of debris between 1 centimeter and 10 centimeters in length orbiting in our space system, and this number is growing."

"In our modern world, we have become more and more dependent on satellites to help us with many things."

"This collision added another 2,000 pieces of junk to the growing pile of space debris. "