Answer to Question 1
ANS: B
Cytokines do not induce macrophages to attack senescent or dying cells. They perform all the other functions listed.
Answer to Question 2
ANS: D
Hundreds of billions of blood cells of all types must be made on a daily basis to maintain normal blood levels of the various cells types. White cells use the bloodstream as a street to get from their site of production to tissue, which is their primary site of function.