Because it's a small scale version of what they're testing and it's helpful to see how the thing may react before going further with testing on a larger scale
Answer:
D. Eukaryote
Explanation:
An organism that has membrane-bound organelles will have more complex organelles like mitochondria, Golgi apparatus, and ER. These are known as Eukaryotes. Additionally, they will have a nucleus that has the DNA coiled inside. Prokaryotes do not have membrane-bound organelle and the DNA floats in the cytoplasm. Most plants and animals are eukaryotes and all multicellular organisms are too.
DNA replicates typically before a cell divides. It follows a series of steps but in general DNA unzips - the base pairs that are 'exposed' are paired up with their matching 'other halves' (A-T and G-C) and you end up with 2 strands of DNA (each strand containing 1 original 'line' and one newly synthesized 'line')
I think that genetic engineering is a good idea because it helps cure deseases that people cant cure, and could possibly cure cancer some day.
Hope my oppinion helped!