Human populations in low-uv environments tend to have lighter skin tones. one explanation is that the selective pressure for dark skin decreases as uv intensity decreases. at the same time, there is selection for lighter skin to absorb more uv radiation, which is needed for vitamin d production. what evidence supports the vitamin d hypothesis for the evolution of lighter skin tones?
a. in general, people with lighter skin tend to be at higher risk of vitamin d deficiency. b. red hair and light skin are typical of people of northern european descent. c. some indigenous peoples living at high latitudes have darker skin, but they tend to eat foods rich in vitamin d. d. people with lighter skin cannot synthesize enough vitamin d in high-uv environments, such as equatorial africa.

Option C

Explanation:

The theory states that the people with the lighter skin tones have the ability to produce more Vitamin D in presence of sunlight. The less the skin deflect UVB, the skin can produce more VItamin D.

This is the reason inspite of being at the higher latitude region some indigenous people having darker skin tone needs to have vitamin D as supplements or eat foods rich in VItamin D.

hence, the correct answer is option C

there are mainly three domains in biological classification namely; archaea, bacteria, and eukarya.

archaea includes all the prokaryotic cells which are characterized by their lipid membranes. they have branched hydrocarbon which is attached to glycerol through an ether linkage.

bacteria includes all the prokaryotic cells, the cell membrane of which are made up of the unbranched fatty acid chain. in addition, they are attached to glycerol through an ester bond.

eukarya includes all the eukaryotic cells, that is, the cells contain a nucleus and other membrane-bound cell organelles.

they can be autotrophic as well as heterotrophic, unicellular as well as multicellular

they include kingdoms like protista, plantae, animalia, fungi et cetera.

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explanation:

question: which statement best describes the different properties of metals?

answer: they are shiny and bend without breaking.

since metals have certain characteristics properties, they include the following: they are ductile, malleable, shiny, hard, lustrous, flexible and they are good conductor of heat and electricity. so therefore, metals are not dull and they are not non-flexible as listed. instead, they are shiny and flexible.

hope this , have a good day. c;