It's A because you basically learn like how to be happy if that makes sense
They are using Scientific evidence because its proven that 85% of the doctors use the product.
It should be Thymine, but I'm not entirely sure. Adenine bonds with Thymine and Uracil.
the medullary cavity or the marrow cavity is the central cavity of bone shafts- where red and yellow bone marrow is stored(and it contains yellow bone marrow)
