Couples who cohabit are characterized by a lower level of commitment when
compared to married couples. Cohabiting couples are two people who live
together but are not married. The form of relationship between the two people
is a loose relationship because it does not have a legal binding and they are
free to separate at any time.
All the other answer choices are still dreamt of by many scientists and engineers. but you always see people wearing prosthetic legs. D is the obvious answer.
