No animal behavior is an exact science, whatever that is, but science is more accurate and precise on human behavior than social science is.
Is human behavior an exact science?
Here is my take on it. Everyone will not react the same under any given situation. Due to imperfection. The apostle Paul said it best: "When I wish to do what is right, what is bad is present with me. I really delight in the law of God according to the man I am in within, but I see in my body another law warring against the law of my mind and leading me captive to sins law that is in my body. Miserable man that I am! So you see there is no way to have human behavior down to a science.