What embryonic layers contribute to the formation of the peritoneum?
A) Ectoderm, mesoderm, and endoderm
B) Ectoderm, endoderm, and endoderm
C) Mesoderm, ectoderm, and ectoderm
D) Endoderm, mesoderm, and ectoderm
E) Endoderm, ectoderm, and mesoderm
Explanation: The peritoneum forms when cells from the three embryonic layers—ectoderm, mesoderm, and endoderm—move into the interior of the embryo during gastrulation, leading to its development.