Elder care or elderly care involves the provision of special care that is unique to senior citizens. Elderly care encompasses special care varying from assistance with daily activities, home care, health care and other special care needed by those, who are in their sensitive phase of life. All such care is provided the senior citizens to enable them live a healthy life at old age, that is free from worry and anxiety.
Based on this information, it can be said that evolution of the frog's body is taking place through natural selection. This selection is based on how "fit" the frog is to his environment.
It means the substance can't mix or dissolve in water. This is because the molecules don't attract to eachother. Oil won't mix with water because it is non polar.