Answer: B. Comparative embryology
Explanation: Good luck! :D
Gel electrophoresis separates fragments on the basis of weight and electric charge. Heavier and/or positively charged fragments don't go as far as lighter and/or negatively charged ones.
The larger mass a star has the shorter its life span will be because since it is so large, the more nuclear energy it has to create to keep it up and running. So the smaller the star the longer its life span and vise versa. Hope this helped!
C. The movement of water from the central vacuoles of cells into the solution