Hamilton’s rule states that: a. altruism evolves only among nonkin.
b. selfish genes swamp altruistic genes.
c. altruistic behavior is favored if the cost to the actor is less than the benefit to the recipient, devalued by the degree of relatedness.
d. altruistic behavior is favored if the benefits to the actor are greater than the costs to the recipients, devalued by their degree of relatedness.

The correct answer is option D.

Explanation:

Hamilton rules state that any trait that helps in benefiting others, B, is multiplied by genetic relatedness, R, which is greater than cot to self, C, it is favored by the process of natural selection.

As indicated by Hamilton's rule, the kin selection makes qualities increment in recurrence when the hereditary relatedness of a beneficiary to an actor multiplied by the advantage to the beneficiary is more noteworthy than the regenerative expense to the actor.

Thus, the correct answer is option D.

answer: - few nutrients

high pressure

low temperatures

explanation: 1. few nutrients:   open-ocean zone is located way far from the land, which is the main source of the essential nutrients.2. high pressure: pressure increases by 1 atmosphere for every 10 meters increase in depth.3. ample sunlight: a large fraction of the sunlight is reflected back to the atmosphere from the sea surface. 4. varying salinity: below the thermocline, the water is isolated from the atmosphere so the salinity remains stable over the year.5. low temperatures:   the temperature of open-ocean zone ranges from a low of -2°c to an average of 17°c

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.