Network managers have long awaited practical voice-over-IP (VOIP) solutions. VOIP promises ease network management and decreases (66) by converging a company’s telephony and data infrastructures into one network. And a VOIP solution implemented at a company’s head-quarters with far-reaching branch offices can (67) tremendous amounts of money in long distance phone bills, provided that solution delivers POTS-like voice (68) over the Internet.
VOIP gateways are designed to convert voice from the (69) domain to the circuit switched domain. VOIP solutions use a digital signal processor (DSP) to process the voice data, preparing the voice sample for transmission by compressing voice and removing jitter. The VOIP equipment must comply with the (70) H.323 standard defined by the International Telecommunication Union, or ITU.

A．framing

B．message

C．circuit

D．packet

人类的大脑细胞具有______的抵抗癌症的能力，不但可以调节人体免疫系统能力，还能______肿瘤细胞的生长。人类实现自主抗癌不再是幻想。
填入横线部分最恰当的一项是( )。

A．显著 减缓
B．潜在 遏制
C．轻微 压迫
D．优异 阻止