If You Think of the Tube- Within- A- Tube Body

Multiple Choice

If you think of the tube- within- a- tube body plan as a pipe with a straw inside, where would you expect to find most of the ectodermal, mesodermal, and endodermal germ layers, respectively?

A) straw; space between pipe and straw; pipe
B) pipe; straw; space inside of straw
C) space inside of straw; straw; space between pipe and straw
D) pipe; space between pipe and straw; straw