The correct option is A 1
An endothermic reaction is any chemical reaction that absorbs heat from its environment.
endothermic or heat-absorbing processes:
melting ice cubes
melting solid salts
evaporating liquid water
converting frost to water vapor (melting, boiling, and evaporation in general are endothermic processes)
making an anhydrous salt from a hydrateforming a cation from an atom in the gas phase
splitting a gas molecule.
conversion of graphite to diamond (2kJ/mole)