Respuesta :
The situational irony refers to an end different that the one expected or planned, in this case Alan Weisman described in this excerpt of "The City Without Us" a kind of weeds that ironically is known as “the tree-of-heaven” and that is also one of the “most prolific exotic species”, however does not good to the city or community due to bad result of his rotting affecting the subway, sidewalks and sewers. The answer is D. weed tree that wreaks havoc on the environment is referred to favorably as the "tree-of-heaven."