The correct answer is (4) Autotrophic organism.
Green plants make their own food by the process of photosynthesis using sunlight. Most of the autotrophs use carbon dioxide, sunlight and carbon dioxide to produce glucose that is used by the plants to obtain energy. Most of the oxygen comes from these organisms and decrease in the number of green plants can lead to several problems due to decrease in the amount of oxygen. Example: green plants, algae, and even some bacteria. This food and oxygen is produced by the action of autotrophic organisms
The answer is option B "temperature." Greenhouse effect is the process of trapping the suns heat in the lower atmosphere. A increase of greenhouse effect would cause surface temperatures to rise. Which then contributes to global warming because of melting the ice bergs in cooler areas on Earth and causing waters to rise and creating storms. It's not option A because the sun gives off heat or harmful radiant waves which doesn't increase carbon dioxide levels. Wouldn't be option D because it would contribute but it wouldn't happen without a increase of temperature. It also wouldn't be option C because oxygen isn't relevant in this case.
Hope this helps.
Answer:
They teach you the purpose of condoms (or you learn the hard way.)
how to prevent stds
Explanation:
That's all I can think of.