There is a sentence that is missing in the paragraph below. Look at the paragraph and decide in which blank (option 1,2,3 or 4) the following sentence would best fit.
Sentence: When people socially learn from each other, they often learn without understanding why what they're copying-the beliefs and behaviours and technologies and know-how-works.
Paragraph: ___(1)___. The dual-inheritance theory ....says....that inheritance is itself an evolutionary system. It has variation. What makes us a new kind of animal, \and so different and successful as a species,is we rely heavily on social learning,to the point where socially acquired information is effectively a second line of inheritance, the first being our genes.... ___(2)___. People tend to home in on who seems to be the smartest or most successful person around,as well as what everybody seems to be doing-the majority of people have something worth learning. ___(3)___. When you repeat this process over time,you can get,around the world,cultural packages-beliefs or behaviours or technology or other solutions-that are adapted to the local conditions. People have different psychologies, effectively. ___(4)___.