Which of the following is most likely the result of an organism having lipids in its body?
A. A walrus stays warm in the cold ocean.
B. A fish moves up the river to spawn.
C. A reptile slows down in colder temperature.
D. A chipmunk buries nuts for the winter.

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.