I think one is carbon dioxide not sure what the other is
Birds like to lay fossils. Salamanders have tails btw.
Hope this helped!
The answer is A because it is in order( idk how to explain but its A)
I know this isn't answering your question but i think you will find it useful to visit the link pasted below. i just visited it and it explains pretty much everything about this.
Saturated fats are bonded together by single bonds, are found in animals, and are solid at room temperature; unsaturated fats are bonded together by double bonds that create a “kink”/bend, are found in plants, and are liquid or oil at room temperature.