Given a scientific question, generate a correct answer to it.

Ex Input:
Shielding should be used when receiving x-rays to limit exposure to what potentially harmful form of energy?

Ex Output:
radiation

Ex Input:
Inside each lymph node is a honeycomb of connective tissue with spaces filled by what?

Ex Output:
white blood cells

Ex Input:
Rising air currents carry water vapor into what?

Ex Output:
atmosphere