You are presented with the question "What allows candles to burn and wax to melt?" and the following answer choices: 
- nektar
 - lids
 - energy
 - sugar
 - heat
 - displays
 - jars
 - power

Now knowing that melting is when solids are heated above their melting point and softer melt point wax is used to produce an even burning candle, choose the best answer.


 

     heat    