Answer:
Option (B)
Step-by-step explanation:
Exosphere is the region of the upper atmosphere of earth and here the amount of air molecules is significantly less, forming a thin layer with certain amount of hydrogen and helium. This layer extends upto a height of about 10000 km and here the particles moves very rapidly, thereby the temperature at this region is relatively high. From the exosphere region the space starts and it is the region in which the artificial satellites are orbiting around the earth.
Thus the correct answer is option (B).