I is answer. Don't open link. It is most likeky unsafe.
Answer:
C) The allele R' is becoming more common in the population.
The continental shelf is a gently sloping feature found at the edge of a continental landmass going seaward from the coast. Rivers that empty into the sea can produce currents that are strong enough to erode the material that builds the shelf. When this occurs channels or submarine canyons are formed. These canyons are deep and dark as no light can penetrate these regions. The canyons often lead out to sea towards the edge of the shelf.
Since it is longer then the food will have more time to digest.
