2013年11月复旦大学历史系和人类学联合课题组，经过对全国各地258个曹姓家谱等各种历史文献进行搜集整理分析，又通过复杂的染色体DNA全序检测法，最终得出曹操不是汉代丞相曹参后人。对此你认为复旦大学得出这一研究成果的基本方法最应该是

A．充分利用并整理了原始资料

B．注意掌握了唯物史观等史学观点

C．充分利用了最新高科技技术

D．收集、整理、研究材料，得出结论

For each blank, choose the best answer from the four choices and write down on the answer sheet.

In (1) the strength of the carrier signal is varied to represent binary 1 or 0. (2) is a system that can map a name to an address and conversely an address to an name. (3) is a three -way handshaking authentication protocol that it’s packets are encapsulated in the point - to -point protocol. (4) is an approach that enables an ATM Switch to behave like a LAN switch. (5) is an guided media which is made of glass or plastic and transmits signals in the form of light.

3（）

A．PPP

B．PAP

C．CHAP

D．LCAP