Even in her early 60s, Theresa has a full head of dark hair with not a hint of gray. When people ask why, she explains that her mother didn't start turning gray until her mid-70s. Which of the following is the likely cause of Theresa's still-colorful hair?
a. life-cycle forces
b. sociocultural forces
c. biological forces
d. psychological forces

The correct answer to the question is c. biological forces.

Explanation:

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

the electromagnetic energy from the sun arrives in the form of visible and invisible light.