The correct answer is - the release of methane from thawed permafrost.
In the past decade it has been noticed that the levels of methane are increasing in the atmosphere, and the biggest ''producer'' of this methane is the melting permafrost. There's huge amounts of methane trapped underground bellow the permafrost. But the permafrost is melting because of the global worming, so the methane is free to come out and go up in the atmosphere.
Answer:D
Explanation:
Both parent are Heterozygous for the sickle cell allele.
Both parent have sickle cell trait in which the both posses one abnormal allele of the hemoglobin beta gene (AS heterozygous genotype)
When two AS parents mate, probability of giving birth to a sickle cell anemia child is 1/4
AS + AS= AA, AS, AS, SS
An environment high in carbon dioxide and high in oxygen induce oxygen to bind to hemoglobin. Another factors are an environment under high pressure and an environment under low pressure.