请教２００２－０５－３０

leadership

２００２－０５－３０

Although all sedimentary rocks contain iron, but the deposits that are richest in iron

consist predominantly of minerals such as iron oxides,carbomates,silicates and sulfides.

请问Ｃ答案，"are richest"为什么是对的？最高级不是＂the richest"　吗？

conquer

这里richest做are后面的表语，所以加不加the都可以

although和but不能连用

leadership

thanks !!!