Answer: Option C) dehydration
Step-by-step explanation:
Dehydration involves the removal of at least one mole of water from a substance which could be solid, liquid or gas. Thus, the unidentified molecule, most likely a solid was splitted to its simpler pieces in a process known as dehydration.
For instance: The dehydration of a compound X will be as follows
X ---> Y + nH2O, where n refers to the number of water molecules lost during dehydration