Answer:
B. Studies why people sometimes don't optimize
Step-by-step explanation:
Behavioral economics is the combination of psychology and economics applied to explain why individuals sometimes behave irrationally and don't make optimal economic decisions.
Behavioral economics takes into account human factors such as emotions, influence etc and cites them as one of the reasons as to why individuals act irrationally sometimes.
For example,most of our buying decision are influenced by what our peers buy and many a times lead us into buying those articles which we don't actually require.
Thus, behavioral economics (C). studies why people sometimes don't optimize.