A – Wrong
Nothing is mentioned about humans in the text.
B – Wrong
The text does not say that traditional evolutionary theory is discredited. Some exceptions are seen when some birds carry out reciprocal altruism in order to receive paybacks in the future.
C – Correct
Some birds carry out reciprocal altruism in order to receive clear paybacks in the future from other birds. Therefore, the birds that do carry out reciprocal altruism do it for their own benefit. This is compatible with the traditional evolutionary theory which suggests that animals are never altruistic.
D – Wrong
The paragraph is not only about birds. It just uses birds as an example ot reciprocal altruism.
E – Wrong
‘Survival of the fittest’ is not relevant to this text.