下列属于内毒素的是（）

A.脂多糖

B.细菌素

C.肠毒素

D.破伤风毒素

E.白喉毒素

The wild mouflon sheep of the island of Corsica are direct descendants of sheep that escaped from domestication on the island 8,000 years ago. They therefore provide archaeologists with a picture of what some early domesticated sheep looked like, before the deliberate selective breeding that produced modem domesticated sheep began.
The argument above makes which of the following assumptions

A．The domesticated sheep of 8,000 years ago were quite dissimilar from the wild sheep of the time.

B．There are no other existing breeds of sheep that escaped from domestication at about the same time as the forebears of the mouflon.

C．Modern domesticated sheep are direct descendants of sheep that were wild 8,000 years ago.

D．Mouflon sheep are more similar to their forebears of 8,000 years ago than modem domesticated sheep are to theirs.

E．(E) The climate of Corsica has not changed at all in the last 8,000 years.