局部兴奋的特点不包括（）。

A.不是全或无

B.不能远距离传播

C.可以相互叠加

D.具有总和现象

E.感受器电位、慢电位、突触后电位、阈上电位均是局部兴奋的表现形式

Questions 53 to 57 are based on the following passage:(10分)To the people of ancient Egypt,life on earth was short.Life after death,however,was eternal. Therefore they built their tombs of stone and they took their possessions with them into another world. The more important the people,the greater the tomb.The Pharaohs were the rulers of the country and when they died they became gods.Many of their tombs remain,and some have become a wonder of the world.These are the pyramids.The purpose of these stone mountains was to protect the burial chamber form the weather and from thieves who might try to steal the gold,jewels and precious possessions placed there to accompany the dead ruler into eternal life.Their shape,with four triangular sides spreading from a single point,represented the rays of the sun.their position on the west bank of the River Nile was where the sun set every day and where they believed it began its journey into the other world.All the burial grounds in ancient Egypt were on the west bank of the river.

Whose Tombs were the largest and the most impressive of all

A．The tribe leaders’tombs.

B．The Pharaohs’tombs.

C．The tombs of those who built them.

D．The rulers’wives.