Answer:
B. hold clear expectations about the way their grandchildren should behave.
Explanation:
The role of grandparents in the studied to have a significant impact on the development of their grandchildren and vice-versa. While talking about companion grandparents they presented their relationship as connected, loving, and playful. For most people, they fit the ideal grandparenting profile but they not get involved with parenting and disciplining of their grandchildren.
A slow change such as continents moving will create differences in ecosystems. This is also the same effect caused by a rapid change such a meteorite striking earth. These two phenomena will create diversity and different living conditions. The slow change however, will give organisms time to adopt giving them a good chance of survival unlike a rapid change which will give most, if not all, organisms little chance to survive.