An antihistamine counters the effects of histamine. which of the following is an effect of histamine?
a. increased blood flow brings more warmth to the area, causing a local "fever" that white blood cells and suppresses microbes.
b. capillary dilation increases blood flow and causes surface redness.
c. increased blood flow brings more white blood cells to the site of injury or invasion.
d. increased blood flow and permeability increase the fluids in the tissues, causing them to swell.

The correct answer will be option-D

Explanation:

Histamines are the nitrogenous compounds which play an important role in providing immunity.

The histamines are produced by the mast cells and basophils which when produced act in the body by causing dilation of the blood capillaries (vasodilation) and then increasing permeability causing the tissue to swell. This produces an allergic reaction.

Antihistamines act by suppressing the binding of the histamine to their receptors thus suppresses the allergic reaction.

Thus, option-D is the correct answer.

answer by yourhope:

answer is

human impact on the environment can be seen in the deterioration of the !

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answer and explanation;

volcanic rocks are igneous rocks which form from lava, molten rock which has been thrust out of a volcano onto the surface of a rocky body such as an asteroid, planet, or dwarf planet.  

plutonic rocks are igneous rocks which form from subterranean chambers of molten rock or magma. plutonic rocks make up the base of continental crust as well as oceanic crust. their slow rate of formation causes them to be coarse grained since there is plenty of time for large crystals to form before the magma solidifies into rock.

the textural difference is that plutonic rocks are more coarse grained than volcanic rocks. plutonic rocks are coarse grained while volcanic are fine grained ; glassey or fragmental. since fine and coarse are adjectives the decision as to whether a rock is fine or coarse grained is generally made on the bases of whether or not the individual crystals can be seen in most if the rock.