Question

question 6
horses evolved from a small sized mammal that ate leaves to a large grazing animal. what change occurred in the environment that led to this shift in the population?
an increase in large areas of grasslands.
an increase in the areas of forests.
an ice age wiped out most of the forests.
an increase in mountainous regions.

Explanation:

Horses evolved to be grazing animals. Grazing animals rely on grasslands for food. An increase in large areas of grasslands would provide the necessary food source for the shift in the horse population from leaf - eating to grazing. An increase in forest areas would support leaf - eating animals more. An ice age wiping out forests doesn't directly explain the shift to grazing (as it doesn't imply a shift to grasslands). An increase in mountainous regions is not relevant to the diet shift from leaves to grass.

Answer:

An increase in large areas of grasslands.