The Mississippi River Today Is a Classic Meandering River

The Mississippi River today is a classic meandering river. 20,000 years ago the Mississippi River was a major outwash channel for the Laurentide ice sheet. What does this suggest about the ancient Mississippi?

A) It probably looked similar to the river today, but was characterized by more dramatic summer floods that occurred every year.
B) It was probably a lush heavily vegetated valley due to the nutrients brought down by the glacial meltwater, producing a swampy landscape with numerous channels.
C) It probably resembled modern rivers in Alaska with a broad braided stream valley that dried up during the winter months, producing winter dust storms.
D) It is impossible to predict what the river might have looked like.