What makes banana’s radio active?

Question: What makes banana's radio active?
- Keywords:
  banana,
  radioactive
Asked by Lilybug005 to David, Eva, Kate, Nicholas, Rachel on 14 Nov 2015. This question was also asked by x_sassy_scientist_x.
- Nicholas Pearce answered on 14 Nov 2015:
  
  Hey,
  
  It is because bananas contain a high level of potassium, which is a tiny bit radioactive. Potatoes carrots and brazil nuts are all also radioactive foods, but I wouldn’t worry about any radiation, the amount is so tiny.

Question: What makes banana's radio active?