This is an example of exchange theory.
In sociology, exchange theory has to do with maximizing benefits while also minimizing costs. When applied to Bill and Cathy's situation, they are taking advantage of each other's skills in order to minimize costs - Bill can cook and Cathy can't (so they can prepare food on their own) and Cathy can repair stuff and Bill can't (so they don't have to get a handyman).
Answer:
the 2nd and 3rd options
Explanation:
as per the undp, development of the health sector also plays a part in the development of a country.
and if a country is developed its people won't be too much engaged in agriculture
