Please help!!
Greyhounds are dogs with long, powerful legs and slim bodies that make them very fast runners. Which of the following best describes how humans were able to engineer this breed of dog?

A). For many generations, these dogs were allowed to run freely in large, open fields.
B). Dogs that were slower than others were given exercise and trained to run fast.
C). Over many years, all the dogs were fed diets high in protein and vitamins.
D). In every generation, only those dogs with the desired traits were allowed to reproduce.

climate change and pollution

answer: grassland biomes are closer to the equator and receive more rain.

grasslands are biomes that are dominated by grasses rather shrubs and trees. savanna are biomes that exhibit grasses, shrubs and small tree as vegetation. grasslands are located near the equator of the earth. these are found in north america. savanna biomes are found in africa, south america, australia and india. grassland exhibit moderate climatic conditions, it receives   amount of rainfall higher than savanna.   therefore, savanna exhibit dry and hot climatic conditions.