The vertebrate digestive system consists of a two-way tube with A. a separate mouth and anus and accessory organs.
B. a one-way tube with a separate mouth and anus and accessory organs.
C. a two-way tube with a separate mouth and anus.
D. a tube with a single opening that serves as mouth and anus.
E. a one-way tube with a separate mouth and anus and no accessory organs.

It's option B.

I'm sure about that.

B. A one-way tube with a separate mouth and anus and accessory organs.

well schools are being forced to embrace computers. unlike their "digital immigrant" teachers, these students are "digital natives", born into a world where technology is an integral part of everyday life. almost every student has access to a multitude of computers, laptops and tablet devices. it would be crazy to assume an assignment would  not be written on computer in this day and age.

don't delete this trying to