请NN及好心人帮助看看，虽然E选项的错误比较明显（have ... in number 啰嗦），但是D选项似乎也不对吧（我觉得has grown 和has reached并列，那么第二个has应该省略呀？）请NN给讲讲D为什么正确，谢谢！
GWD-24-9
Part of the proposed increase in state education spending is due to higher enrollment, since the number of students in public schools have grown steadily since the mid-1980’s and, at nearly 47 million, are at a record high.
A.enrollment, with a number of students in public schools growing steadily since the mid-1980’s and, at nearly 47 million, reaching.
B. enrollment, with a number of students in public schools growing steadily since the mid-1980’s and, at nearly 47 million, reaching.
C. enrollment: since students in public schools have grown steadily in number since the mid-1980’s and, at nearly 47 million, have reached.
D. enrollment: the number of students in public schools has grown steadily since the mid-1980’s and, at nearly 47 million, has reached.
E. enrollment: students in public schools have grown steadily in number since the mid-1980’s and , at nearly 47million, are at
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