Questions

Processes that require or give off heat will be limited to changes of state, known as phase changes, and changes in chemical constitution, or chemical reactions. Changes of state involve a solid melting, a liquid freezing, a liquid boiling or a gas condensing.

An exothermic process is one that gives off heat, which is transferred to the surroundings. An endothermic process is a reaction which heat has to be supplied to the system from the surroundings.

Here in all the given options, heat is taken away from them to change there phase. 

Liquid to Solid --- Freezing

Gas to Liquid --- Condensation

Gas to Solid --- Deposition 

are all examples of exothermic processes.

The given letter equation tells that,

Wives of Henry the Eighth.

Antisnake venom: In the Hoffkine Institute at Bombay snake venom in mild dose is injected into horses and the horses are induced to produce anti-venom bodies. These are extracted and used in cases of snake bites.

Mason Dixon Line