A. Bacteria are single-celled.
I think it would be this because humans have way more than one cell, and the other ones are the same as us.
Just guessing
Germ layer is a primary layer of cells found in the embryo. The three primary germ layers that generate most of the cells in the developing mammalian forelimb are ectoderm, mesoderm and endoderm.
Ectoderm forms the outer component of a mammalian body such as skin, hair, etc. Endoderm forms the inner layer that comprises of the linings of digestive system, lungs and thyroid. Mesoderm is the middle layer that forms the skeletal system, heart, etc.
Neural tube is generated by the inward folding of the ectoderm. This process is called neurulation. Ectoderm also forms neural crest.
A new area of Science promotes experimentation from a different point of view
1: D
2: B
3: B
4: C
5: D
8: A
9: D
10: A