28. Most of the world's coastal cities were established during the last few millennia, a period when global sea level has been near constant. Since the mid-19th century, sea level has been rising, most likely as a result of human induced climate change. During the 20th century, sea level rose by roughly:(A)1.5 to 2.0 mm/year(B)1.5 to 2.0 cm/year(C)10 cm/year(D)50 cm/year