You are presented with the question "what keeps humans warm?" and the following answer choices: 
- Animal fur
 - Solar energy
 - wind
 - radiation
 - Evaporation
 - snow
 - magnets
 - exoskeleton

Now knowing that preventing the transfer of heat from an organims 's body causes that organism to keep warm and radiation is the major method of heat transfer warming Bob's face, choose the best answer.


 

    radiation     