Choose your reply from the options at the end. Does "The small shelly fossil Cloudina, from 549 to 542 million years ago, has been classified by some authors as an annelid, but by others as a cnidarian (i.e. in the phylum to which jellyfish and sea anemones belong)." contain the correct answer to "When did Cloudina exist?"
Possible answers:
(A). yes.
(B). no.
(A).