where would you expect to not find many trees? a. taiga b. chaparral c. grassland d. both b and c

I would go with B) Chaparral because with C) its in the name grasslands and trees mostly grown near grass and if u look in this picture on the left, that's grasslands and most of trees grow there and if u look in the middle that's a taiga and lots of trees grow there as well but in the last picture on the right u can rarely find trees there, now some trees can be there, but mostly none will be there due to the weather or environment . Hope this helps.

I would say D, for both B and C.
Taiga biomes often have plenty of trees, so A is obviously no the answer.

Chaparral biomes have very few trees, so B would fit into the answer;
However, grassland biomes are covered mostly by grass. They are prone to fires, preventing too many trees from growing. Due to this knowledge, I can draw the conclusion that the answer B and C will work, meaning the answer is D.

They are all in a iving organism.

This is the most closely resembles the model.