-4 has one because it is on the line
D. ice core samples for the arctic and anarctic
Answer:
"Survival of the fittest" is a phrase that originated from Darwinian evolutionary theory as a way of describing the mechanism of natural selection. The biological concept of fitness is defined as reproductive success.
Explanation:
The increase of carbon dioxide in the atmosphere creates a greenhouse effect.
To explain this usually some sunlight is reflected back into space while some is absorbed by the earth keeping the planet warm. However the increase in greenhouse gases such as carbon dioxide prevent the light from reflecting back into space and this light becomes trapped causing the earth to heat more then it should. You can almost think of the trapped heat from the greenhouse gases as a blanket around the earth trapping the heat in.
Answer: Skeletal system Explanation: