The world is an illusion is the only possible answer.
Explanation:
Hindu priests do not claim to be able to spek to god, and since they are polythiestic they do not believe in one god. They do believe in a specific set of gods however so they would not believe that god is formless. They also believe in Karma and reinecarnation so ``We only live once`` would not be a viable answer either. To my knowlage ``The world is an illusion`` is not a core hindu belief either so I would question your teacher about that.
The larger mass a star has the shorter its life span will be because since it is so large, the more nuclear energy it has to create to keep it up and running. So the smaller the star the longer its life span and vise versa. Hope this helped!