Step-by-step explanation:
Social Stratification is basically the social differentiation, where the people or group of people are classified or arranged according to strata, most commonly on the basis of their income, wealth, power and social status.
So now answering the questions asked in the question:
My family belongs to an Upper Class.
Yes the social standing of my parents are different from their parents or grandparents, as their ancestors belonged to a middle class status.
There were no important social traits handed over by our forebears to us.
Yes almost every marriage was exogamous in the history of our family. My family used to marry outside of the family. There were no such rule to marry within the family.
And yes my family exhibit the status consistency, as they grew from lower middle class to upper class gradually. The consistency was the gradual improvement in the social classes.