asp viper vs horned viper

Question
My class assignment is to research each snake and try to decide which Cleopatra would have chose to end her life. Really- this is hard with just general information. Can you help point me in the right direction?

Answer
Hi Noah,
  The accepted snake is an asp. There is much debate with some saying it was an Egyptian cobra. Still others argue that there were enough poisons around at the time to allow her to commit suicide by a far less painful means. In situations like this, the simplest answer seems to be the most likely. I would guess that Cleopatra killed herself with known poisons and the snake story is folklore. Google "what snake killed Cleopatra" and read all the evidence.