Answer:
In an ecosystem, energy enters in the form of solar energy or light energy from sun. Solar energy is transformed into various other types of energies like kinetic energy, chemical energy, potential energy, etc; but it eventually leaves the ecosystem in the form of heat energy.
To prevent cancer, over exposure to radiation
The earth is surrounded by <em>a layer of</em> gases called the <em>atmosphere</em>. The atmosphere is very <em>important </em>to life on <em>Earth</em> and does many <em>things</em> to help protect life and help<em> life </em>to survive.
The atmosphere absorbs the <em>heat</em> from the <em>Sun </em>and keeps the heat <em>inside</em> the atmosphere helping the <em>Earth </em>to stay warm, called the <em>Greenhouse </em>Effect.
B is the answer :) have a great day!