Which of the Following Is a Reason Why Great-Grandparents Do

Which of the following is a reason why great-grandparents do not have close relationships with their great-grandchildren?

A) Great-grandparents often lack the physical and psychological stamina for their great-grandchildren.
B) There may be too many great-grandchildren, and, therefore, great-grandparents do not have an interest in any specific great-grandchildren.
C) Great-grandparents lack interest in being involved in raising great-grandchildren and, therefore, they don't build relationships.
D) Great-grandchildren may remind great-grandparents of their mortality.