Answer:
A is the correct option
Explanation:
In the pharmaceutical industry, bacteria are used to produce antibiotics, vaccines, and medically-useful enzymes.
The development of the human embryo follows fertilization, and continues as fetal development. By the end of the tenth week of gestational age the embryo has acquired its basic form and is referred to as a fetus. The next period is that of fetal development where many organs become fully developed.
The germinal layers that give rise to the digestive system is Ectoderm, Endoderm, Mesoderm, Respectively.
