The correct answer is letter C, in most primates, the inability to move the ear has been replaced by the ability to stand upright on two legs. This is because movement was much of a need to these primates than hunting for food. They needed to be agile to locate specific places where sources of food are abundant.
A good vector to genetically altered respiratory cells might be A VIRUS THAT HAS BEEN GENETICALLY ALTERED TO CARRY NORMAL HUMAN DNA.
Gene therapy is a medical method of treatment which uses genes to prevent or treat diseases. The method is used to correct the defects in genes which is causing a disease. In order to insert a normal gene to replace the defective one, a vector, which will carry the gene is needed. The vector that is usually used in this case is a virus, which has been doctored to carry a normal human DNA.
