Almost the entire system of an embryo is made of cartilage,
whereas that of an adult is mostly made of bones.
<span>An </span>embryo<span> <span>is a
multicellular diploid eukaryote in an early stage of embryogenesis, or
development. In general, in organisms that reproduce sexually, an </span></span>embryo<span> develops from a zygote, the single cell
resulting from the fertilization of the female egg cell by the male sperm cell.</span>
<span>Biologically, an </span>adult<span> is a human being or other organism that has
reached sexual maturity.</span>
The correct answer between all
the choices given is the first choice or letter A. I am hoping that this answer
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