题目选项分析

A newly released study on the tectonic plates forming the Pacific basin indicates that by the time they shift even a few miles, a vast percentage of the coastline, which is currently a home of the major world cities, will have already become entirely submerged due to global warming

A newly released study on the tectonic plates forming the Pacific basin indicates that by the time they have shifted even a few miles, a vast percentage of the coastline currently home to major world cities already will have become entirely submerged because of global warming