OG 89 请教.

89.   A recent national study of the public schools shows that there are now one microcomputer for every thirty-two pupils, four times as many than there were four years ago.

(A) there are now one microcomputer for every thirty-two pupils, four times as many than there were

(B) there is now one microcomputer for every thirty-two pupils, four times as many than there were

(C) there is now one microcomputer for every thirty-two pupils, four times as many as there were

(D) every thirty-two pupils now have one microcomputer, four times as many than there were（C）

(E) every thirty-two pupils now has one microcomputer, four times as many as

为何题中答案最后要用THERE WERE, 只有一个ONE COMPUTER 呀,

请教各位了.

there were 后面类似于是the computers for pupils

understand?