D) Methanogen is the awnser
Answer:
C
Explanation:
Because between the earth and sun is empty space (vacuum) transfer of heat from the sun to earth can only occur through radiation- because convection and conduction require a medium. The is the same process that warms your hands when you place them beside a fire. When you put your hands above the fire, they are warmed through convection.
It is mostly glass and fiber glass
Environmental scientists are using GPS ( It is effective but expensive) aerial monitoring (Quick but not the easiest), RFID tags, (mostly for long-term monitoring) and hidden cameras are used to study polar bear behavior without interruption to their environment.