William harvey discovered circulation. first, as he tightened a bandage around an arm, he noticed that the fingers turned blue and cold. then, he used a less tight bandage and noticed that the hand swelled. with further research, what conclusion could he make?
a. the blood moving toward the hand contains oxygen.
b. the blood moving away from the hand picks up oxygen.
c. veins carry oxygenated blood and are deep in the skin.
d. arteries carry deoxygenated blood and are deep in the skin.

Correct A). The blood moving toward the hand contains oxygen.  

He concluded that '' the blood moving towards the hand contains oxygen''. The blood contains oxygen and nutrients that are utilized by the body to perform various cellular activities. When the band was tightened the blood circulation stop, and blood is not able to supply nutrient and oxygen to the cell, as a result of that it turns blue and cold. But when the bandage is loosened it supplies blood and nutrients that rectify the situation.

Hence, the correct answer would be option A.

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.

the answer is c most of the fortnite players usually buy v bucks to get the battle pass and other cosmetics but some players who are referred to as "no skins" don't   buy skins and are usually noobs.

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