Which relatively flat feature of the ocean floor is in the open ocean and borders the continental shelf? abyssal plain mid-ocean ridge continental slope deep-ocean trench

The answer would be:

Abyssal plain

Here is more about this feature:

Abyssal plains are flat wide areas of the ocean floor. You can find these features in between a continental rise and a mid-oceanic ridge. These plains are covered in sediment and are found deep down the ocean floor. They are typically featureless, but they sometimes have hills as well, and the hills are called Abyssal hills.

•there must be variation for the particular trait within a population.

•the variation must be inheritable (that is, it must be capable of being passed on from the parents to their offspring).

•individuals with one version of the trait must produce more offspring than those with a different version of the trait.good

explanation:

black

lasagna

lunch

math