Answer:B) homologous chromosomes trade pieces of dna
Explanation:
Crossing over occurs between two homologous chromosome of sisters chromatid. Crossing over leads to exchange of genetic material between the two sister chromatids leading to recombination.
Transcription<span> is the process of converting the message in </span>DNA<span> into </span>mRNA<span>, this is where </span>mutations<span> can first occur. </span>Mutations<span> at the level of </span>DNA<span>can affect the production of </span>proteins<span> in the long run.</span>
The best answer is D, birds.
For more information and details on the way a bird's respiratory system works:
https://asknature.org/strategy/air-flow-patterns-facilitate-efficient-gas-exchange/
