What Makes the Observations Conducted by Social Scientists Different from the Kinds

What makes the observations conducted by social scientists different from the kinds of observations that anyone might make in the course of a day? Social scientists

A) will only sample people from their own culture.
B) make sure to observe a random sample of people.
C) observe and code behaviours according to prearranged criteria.
D) always rely on technology (e.g., hidden cameras or tape recorders) to record behaviours.
E) make it a point never to interact with the people they are observing.