In such a world, the chances that the human species would survive are next to zero, because emotions are the basic instrument of our survival and adaptation. Emotions structure the world for us in important ways. As individuals, we categorize objects on the basis of our emotions. True we consider the length, shape, size, or texture, but an object's physical aspects are less important than what it has done or can do to us—hurt us, surprise us, anger us or make us joyful. We also use categorizations colored by emotions in our families, communities, and overall society. Out of our emotional experiences with objects and events comes a social feeling of agreement that certain things and actions are "good" and others are "bad", and we apply these categories to every aspect of our social life—from what foods we eat and what clothes we wear to how we keep promises and which people our group will accept. In fact, society exploits our emotional reactions and attitudes, such as loyalty, morality, pride, shame, guilt, fear and greed, in order to maintain itself. It gives high rewards to individuals who perform. important tasks such as surgery, makes heroes out of individuals for unusual or dangerous achievements such as flying fighter planes in a war, and uses the legal penal (刑法的) system to make people afraid to engage in antisocial acts.
The reason why people might not be able to stay alive in a world without emotion is that _______.

A. they would not be able to tell the texture of objects
B. they would not know what was beneficial and what was harmful to them
C. they would not be happy with a life without love
D. they would do things that hurt each other's feelings