一道语法题

XIAOYUE78

12． At its center, the sun has a density of over a hundred times _________ and a temperature of 10 to 20 million degrees centigrade.

(A) that of water

(B) of water

(C) than that of water

(D) water

为什么是A？我选了C

efficiency

如果选C的话,than 前面必须要有比较级

应该选A