Answer: layer c is oldest but I can see all of the options
Explanation:
Get used to sleeping and in that order
The three grains are rice, wheat, and corn
Rice is the main grain used in places such as Asia ans SEA, corn is mostly used in the Americas, while wheat is mostly found in European countries.
The channel proteins and carrier proteins allow molecules to pass through the semipermeable cell membrane in order to maintain homeostasis. Hope this helps! :)<span />