gwd-13-8

A new hair-growing drug is being sold for three times the price, per milligram, as the drug’s maker charges for another product with the same active ingredient.

1. as
2. than
3. that
4. of what
5. at which

我选E，没有charge of somethings for sth

只有charge XX for sth

我想可以使charge for sth at the price of ..

你理解错了应该是the price of what

不是charge of,因为比较的是价格。eg:

1/6 times of the asking price

那更不对了

如果是price of what

what应该指代标价的东西

从句明显是charge的