请教一个语法模拟题

The electronics company has unveiled what it claims to be the world's smallest network digital camcorder, the length of which is that of a handheld computer, and it weighs less than 11 ounces.

a. to be the world's smallest network digital camcorder, the length of which is that of   a handheld computer, and it weighs

b. to be the smallest network digital camcorder in the world, which is as long as a handheld computer, weighing

c, is the smallest network digital computer in the world, which is as long as a handheld computer, and it weighs

d. is the world's smallest network digital comcorder, which is as long as a handheld compiter and weighs

e. is the world's smallest network digital camcorder, the length of which is that of a handheld computer, weighing

答案是d, 我选a. 我知道a 的唯一缺陷是it 指代不清，但相对d 在 has unveiled what it claims 后用is 是个小错呀。实在困惑d 的结构，请nn 指教，先谢了。

The electronics company has unveiled [(what it claims) is the world's smallest network digital comcorder], which is as long as a handheld compiter and weights less than 11 ounces.

你没有读懂。如果是A，the company has unveiled what it claims to be...那么就不是what而是that了。

谢楼上zenger gg,但可否帮忙分析此句结构? 难道 The electronics company has unveiled 可直接作主语，说成The electronics company has unveiled... is...而不用what引导词 说成 What the electronics company has unveiled ...is ...? 并且what it claims 在此句中作何成分，插入语吗？

万分感谢！