Certain trees in fact produce seeds only when fire heats them if the fire removes thick shrubs and undergrowth the water supply increases aiding other plants and local animals fire also may kill predatory insects or pest that live on and damage otherwise healthy trees

Which set of context clues best points to the correction definition of undergrowth in the second sentence
A. Seeds , fire , animals
B. Water, plants, animals
C. Insects, pests, fire
D. Thick shrubs, plants, trees

The correct answer is D. Thick shrubs, plants, trees. The context clues in this set point to the correct definition of undergrowth because it states that fire removes thick shrubs and undergrowth, which implies that undergrowth refers to the vegetation that grows beneath or among larger plants, such as shrubs and trees.