A:as more than three times many
B:more than three times many a
C:more than three times as many
D:three times as more than many
五年前,小张在股市低迷时购买了某上市公司的股票,一直持有到今年才卖出。该股票为他带来了3万元的收益。这一收益的来源是( )
①上市公司的利润 ②商业银行的利息
③证券公司的利润 ④股票的买卖差价
选出下列文学常识表述完全正确的一项( )。