Final answer:
A component of the primordial embryo is connective tissue, which is derived from the mesodermal layer of the embryo. The first connective tissue to develop is mesenchyme, the progenitor of all future connective tissues in the organism.
Step-by-step explanation:
A component of the primordial embryo is embryonic connective tissue. During embryonic development, connective tissues derive from the mesodermal layer of the embryo. The first connective tissue to develop in the embryo is mesenchyme, which is the stem cell line from which all connective tissues are later derived. This includes various structures such as facial cartilage, ribs, and lungs. Therefore, among the options given, connective tissues are a component of the primordial embryo.
It's important to note that the other options, such as neural tissues, muscular tissues, and epithelial tissues, also play a significant role in embryonic development but are derived from different germ layers. The neural tube gives rise to the nervous system, muscle tissues originate mostly from the mesoderm, and the ectoderm forms both the integumentary system (skin) and the nervous system, while epithelial tissues can originate from any of the three germ layers: ectoderm, mesoderm, and endoderm.