A symbiosis is an evolved interaction or close living relationship between organisms from different species, usually with benefits to one or both of the individuals involved.
The answer would be D. variation
Answer:
Natural forces don’t have a strong effect on recent global temperatures. The natural forces line begins to drop around 1950 and does not track with the observed temperature line. On the other hand, the human effects line rises upward with the observed temperatures, so it’s a stronger effect. Solar radiation falls into the category of natural forces.
Explanation: This is the exact answer so I recommend changing it up a little bit. :)