鱼缸里的金鱼不停地大口吞水，鳃盖总不停地张合这主要是鱼在（ ） A．吞咽食物 B

下列有哪个选项是正确的

A．色觉是视网膜视杆细胞的一种功能，属于黄斑的功能

B．色盲分先天性和后天性两种。先天性多见于性连锁隐性遗传病，女多于男

C．暗光的辨认是视网膜视锥细胞的功能，分布于周边视网膜，接受暗光刺激产生视兴奋

D．在外界无光线刺激下出现的视觉称闪光视觉，常见于视网膜脱离、急性视网膜脉络膜炎、眼球外伤

E．视物变形指物像扭曲变形，或变大或变小。常发生于视网膜病变患者，如视网膜皱缩患者之视物变形变小

白蚁分泌的蚁酸是一种酸。下列建筑材料最不容易被蚁酸腐蚀的是

Ａ．钢筋     Ｂ．铜制品       C．大理石        D．铝合金

16个处理器编号为0~15，采用PM2+3单级网络互连，与13号处理器相连的处理器号是（）。

A.5

B.1

C.7

D.14

格式合同

IP multicasting is a set of technologies that enable efficient delivery of data to many locations on a network. Rather than making multiple copies of a message intended to be distributed to multiple recipients at the (71) of origin of a message, multicasting initially sends just one (72) and does not copy it to the individual recipients until it reaches the closest common point on the network, thereby (73) the bandwidth consumed. Network performance is significantly (74) because it isn’t bogged down with the processing and transmission of several large data fries; each receiving computer doesn’t have to (75) the transmitting server for the file.

A. pointB. bottomC. head D. sight