Lasting genetic similarities make the two bears biological sister species, more closely related to one another than to any others. ... But Ursus maritimus has also evolved to match its polar environment, growing a longer snout than brown bears' and larger, paddle-like paws, both of which aid polar bears in hunting seals.
I would say it's A because it sounds like the most important one.
Gel electrophoresis is a technique used to separate DNA fragments (or other macromolecules, such as RNA and proteins) based on their size and charge. Electrophoresis involves running a current through a gel containing the molecules of interest.
You can say it as "Constituent Particles" in another term..
If both parents have type o, the child will also have type o, if parents are both type O the children will only inherit type O since type A and B are dominant over type O
