阅读下面长句，回答6-8题What is questioned is whether a country like Britain has a chance, assuming it has the will, to succeed where so many have failed and even assuming that it has, should it make the tremendous effort and take substantial financial risk of trying to leap- frog into leadership in entirely new technology or whether it should take softer opinion of merely catching up with the rest of the industrial world.6.“What is questioned ... “该成分属于?A.表语从句 B.主语从句（填A或B即可）