The air above Earth's surface is at different temperatures. What is responsible for this difference in tempeture?

Would really appreciate it, i have an idea but not completely sure

During crossing-over, a. genetic material is exchanged between nonsister chromatids, resulting in new combinations of alleles. b. nonsister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles. c. one homologous chromosome of a tetrad is exchanged with another tetrad, resulting in new combinations of alleles. d. sister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles. e. genetic material is exchanged between sister chromatids, resulting in new combinations of alleles.

Which of the following terms would bb represent in an organism? a.phenotype b.genotype c.genetics