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three portions of a blood sample show clumps in anti-a serum, but not anti-b or anti-rh sera.
which blood type does the test indicate?

a. a negative (a-)

b. ab positive (ab+)

c. b negative (b-)

d. o negative (o-)

If you add a drop of anti-A serum and it clumps the blood type has blood type B markers that will fight off the A serum making the blood type B  

I got this because...  

there is A, B, AB, and O blood  

A has anti-B clumping proteins  

B has anti-A clumping proteins  

AB has no clumping proteins  

O has anti-A, anti-B, and anti-AB clumping proteins  

so the only on one with anti-A clumping proteins is blood type B  

hope this helps :)

the electromagnetic spectrum includes, from longest wavelength to shortest: radio waves, microwaves, infrared, optical, ultraviolet, x-rays, and gamma-rays.

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