With the development of modern society, E-mail as well as telephones     an important part in daily communication.

A．have played

B．is playing

C．are playing

D．had played

投资者如需将登记在证券登记系统中的基金份额转托管到TA系统(基金份额由证券营业部转托管到代销机构、基金管理人)，或将登记在TA系统中的基金份额转托管到证券登记结算系统(基金份额由代销机构、基金管理人转托管到证券营业部)，应办理系统内转托管手续。( )