The Root Systems of Trees in Tropical Rain Forests Expand

Multiple Choice

The root systems of trees in tropical rain forests expand outward from the tree because

A) the trees are very short and do not need deep roots.
B) the ground temperatures in tropical forests are too high to allow for deep roots.
C) there is a shortage of rainfall in the region tends to prohibit effective plant growth.
D) the ground layer of vegetation in tropical forests is so thick so the roots extract nutrients from the vegetation.
E) the mineral content of the soil is shallow and hence roots expand laterally rather than vertically to exploit the shallow nutrient layer.