For the first time in the modern era, non-Hispanic Whites are officially a minority in California, which amounts to a little less than half the population of the state, down from nearly there-quarters only a decade ago.
which amounts to a little less than half the population of the state, down from nearly three-quarters only a decade ago
which amounts to a little less than half the population of the state, down from a decade ago, when it was nearly three-quarters
and that amounts to a little less than half the population of the state, down from a decade ago, when they were nearly three-quarters
amounting to a little less than half the population of the state, down from nearly three-quarters a decade ago
amounting to a little less than half the population of the state, down from what it was a decade ago by nearly three-quarters
b,c 中黄色部分是否都是修饰不清楚??? 特别是down from a decade ago, 可以修饰state, 也可以修饰when 从句。 it 则是指代不明确的