Answer:
microsystem
Step-by-step explanation:
Microsystem -
Urie Bronfenbrenner in the year 1979 , developed the most famous ecological systems theory , which helps to explain the external factors which determines the growth and development of a child.
According to microsystem , the child development is best analysed by studying the nearby environment i.e. the people surrounding the child .
As the environment where the child is living , plays a major role in the process of development.
Hence, from the given options the correct term is microsystem.