Which of the following is the correct description of the pia mater?

A) The layer of the meninges that is thin and weblike
B) The innermost layer of the meninges
C) The layer of the meninges that is much thicker and tougher than the others
D) The outermost layer of the meninges
E) The middle layer of the meninges

Derivatives of the mesoderm include ________.

A) glands of the digestive tract
B) nervous tissue
C) skeletal system
D) none of the above