What is the origin of smooth troughs (T on this figure)cutting across the landscape in the Great Lakes area?
A)the areas were covered by soft marine sediments
B)a huge flood coming from Iowa flowed toward the Great Lakes
C)glaciers carved the smooth troughs
D)all of these

Question

What is the origin of smooth troughs (T on this figure)cutting across the landscape in the Great Lakes area? 
A)the areas were covered by soft marine sediments 
B)a huge flood coming from Iowa flowed toward the Great Lakes 
C)glaciers carved the smooth troughs 
D)all of these

Quizplus · Accepted Answer

The smooth troughs (T on the figure) were likely carved by glaciers during the last ice age.

What Is the Origin of Smooth Troughs (T on This