For a long time, the fact that prehistoric people made【10】was considered to be one of the major【11】distinguishing them from other creatures.【12】pointed out earlier, I have watched chimpanzees【13】grass stems in order to use them to probe for termites. It is true that the chimpanzee does not【14】tools to "a regular and set pattern" —but then,【15】people, before their development of stone tools, undoubtedly poked around【16】sticks, and straws, at which stage it seems【17】that they made tools to a set pattern either.
It is because of the close【18】in most people's minds of tools with humans【19】special attention has always been focused upon any animal able to use an object as a tool: but it is important to realize that this ability, on its own, does not necessarily indicate any special intelligence in the creature【20】
(1)

A. species
B. specie
C. speciman
D. specimen