placement of the phylum Platyhelminthes in the phylogenetic tree differs between a morphologically based phylogeny and a molecular based phylogeny. Which of the following statements best describes the interpretation based on molecular phylogeny?
A. Modern Platyhelminthes do not have a coelom but did originate from an ancestor that had one.
B. The Platyhelminthes clade separated from other clades before coeloms evolved and consequently Platyhelminthes have never had a coelom.
C. Platyhelminthes originated from ancestors with a coelom and have retained it to the present time.
D. Platyhelminthes evolved from an ancestor without a coelom but developed one during the course of their evolution.
E. Some Platyhelminthes have a coelom but others do not and it is difficult to conclude anything about its evolution within the clade.
A. Modern Platyhelminthes do not have a coelom but did originate from an ancestor that had one.
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