Which of the following contains the greatest number of unipotent stem cells? A. 3-day-old embryo
B. Adult
C. Blastocyst
D. 6-week-old embryo

The answer is atmosphere. there are four spheres of the earth: 1. geosphere (from greek word 'geo' = ground), 2. hydrosphere (from greek word 'hydro' = water), 3. biosphere (from greek word 'bio' = life), and 4. atmosphere (from greek word 'atmo' = air). a magnetosphere is a region of space around astronomical objects controlled by the magnetic field of that object. through the process of elimination, since lightning is present in the air, it can be found in the atmosphere.

If you get a map and put the countries a states all together it forms all one piece you can also tell because of the earth quakes