Answer:
When marshmallows are toasted, a chemical change occurs. The sugar molecules in the marshmallow are being changed into carbon (1). Sugar can be changed into water molecules. ... The flame on stage - oxygen diffuses to the surface of the marshmallow from the surrounding air.
Option 2, Br. I'll go over why all other three options are incorrect.
Option 1 - Krypton is a Noble gas, and so it doesn't need to accept electrons since it has an octet.
Option 3 and 4 - Both Calcium and Barium are alkaline earth metals, and give away electrons, since they only have 2.
-T.B.
B) Exothermic
The reaction released heat energy to its surrounding, thus, it was exothermic.
"exo" is to expel or put outside
"thermic" means heat
Answer : DNA (if im wrong please correct me)