Concept:To round to one decimal place, look at the second decimal digit (hundredths place).Explanation:In 0.9875, the first decimal digit is 9 (tenths place).The next digit is 8 (hundredths place).Since 8≥5, we increase the tenths digit by 1.9+1=10, so the tenths digit becomes 0 and we carry 1 to the units place.Thus, 0.9875 rounds to 1.0 to one decimal place.Answer:B. 1.0