A chair made of steel is stronger though costs much more than made of wood.A. thatB. on

问题补充：

A chair made of steel is stronger, though costs much more, than made of wood.

A. that

B. one

C. it

D. those

答案：

A. that

(答案→)B. one

C. it

D. those

解析：考查代词。That指代可数名词单数和不可数名词，后面必须有定语修饰，表示特指。One指代可数名词单数，表示泛指；it指代上文出现的同一事物；those指代可数名词复数形式，后面必须有定语修饰，表示特指。本题One指代a chair.句意：一个铁做成的椅子尽管更贵，但是却比木头制成的椅子更牢固。故B正确。