问道语法题

the lenses in an optical microscope bend the light psaaing through a specimen to form an image of that specimen that is much larger_____actually viewed.

(A)than it
(B)than the one

这两个选项怎么选？

另，today what little fossil ivory remains comes from Alaska这句话是什么意思

http://forum.chasedream.com/dispbbs.asp?boardid=58&star=2&replyid=596400&id=68285&skin=0&page=1这里有,讨论过的,

请JJ提问时留意一下区有语法区的域,顺便看一下提问格式,置顶帖子里有,谢谢