Temperature is a measure of "Molecular movement"
In short, Your Answer would be Option B
Hope this helps!
The Krebs cycle uses acetyl CoA as a reactant.
You did not include the statements but since magnesium chloride is ionic substance that we know that magnesium and chlorine formed an ionic bond. Therefore your statement most likely will talk about how one magnesium atom gave up 2 electrons while two chlorine atoms took 1 electron. The reaction looks like Mg+2Cl⇒MgCl₂.
I hope this helps. Let me know in the comments if anything is unclear.
B. eating the right amount of calories each day
for a, you need proteins,veggies and calories to survive, as each does a specific job such as glucose and protein being created, etc.
For c, you can have at least 1 item from each food group each day, but you can still have too much of something and thats harmful.
For d,getting 100% calcium only works with calcium, and you can do anything with the other foods.
For b(which is correct), people usually eat an excess of calories, and that mainly controls your weight. Now other food groups can also affect you if you have too much, but people tend to have too much calories, so getting the right amount of calories is the best choice