A diagnostic test for tuberculosis (TB) involves injecting antigen (from the bacterium that causes TB) under the skin and then waiting a few days for a reaction to appear. This test is NOT useful for diagnosing TB in AIDS patients. Explain why

The biome pictured above is found in areas such as kenya and south africa. the land is grass-covered with very few trees and gazelles and other grazers are common here. why does this biome have a low population of trees? a) large grazing animals destroy the trees. b) it is a deforested rainforest with poor soil. c) it has high temperatures and low precipitation. d) it has a long rainy season followed by flooding.