use the sentence to answer the question
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 pests that live on and damage otherwise healthy trees.
which set of context clues best points to the correct definition of undergrowth in second sentence?
"insects, pest, fire"
"seeds, fire, animals"
"thick shrubs, plants"
"water supply"