The third alternative is correct (C).
There is incorrect information that the Lemming commit collective suicide.
By the necessity of eating, the lemminges move in mass, behind food. In nature, any migration involves some dangers and death is always a threat on the prowl. Lémmingues simply act according to their instinct for survival. One animal follows the other. In the famous case is the precipice, what happens and a herd effect. One individual shifts and falls, and others follow. Talking about suicide would involve a will. Therefore, the mass suicide of lémmingues is false.
