The right answer is B active immunity.
For information, there is no complete immunity and incomplete immunity in immunology.
Active immunity is a form of immunity that protects the body through the production of antibodies when exposed to a first infection or vaccination.
This type of immunity is persistent. Example of measles: previously safe measles viruses are applied during vaccination.
Answer: D. Gradually, as generations of elephants continued to selectively use and develop their trunks.
Explanation: Lamarck believed that organisms pass on traits to their offspring that they had acquired through use or diuse during their lifetime. In this example, the theory would be that over time, elephants used their trunks in such a way that they became long and powerful.
your respiratory system collects oxygen which is handed to your blood in your cardiovascular where it is pumped all over the body where it is needed.
