<span>A(n)PRIMITIVE CHARACTER is one present in the common ancestor and all members of the group
Primitive character is also known as ancestral character in phylogenetics. It is defined as a characteristic that has undergone little change since time immemorial and is inherited from a common ancestor of a clad.
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For the answer to the question above, I think that <span>the initial titer that has been done to her may have been done too early in the infection that detectable levels of antibody were not present yet so that's why they have to repeat it.</span>
I believe the answer would be sugar