Identify the two extra-embryonic membranes and the three different regions of the endometrium at week 10 of development in the following diagram.
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a. ___
b. ___
c. ___
d. ___
e. ___
Syncytiotrophoblast and lacunae.
Ectoderm and syncytiotrophoblast.
Extraembryonic mesoderm and syncytiotrophoblast.
Extraembryonic endoderm and syncytiotrophoblast.