question: Where do the progenitor cells for bone fracture healing float around?
choices.text: lymph system digestive tract Natural world Moist habitats properly stored bone marrow recyclable biceps
choices.label: A B C D E F G H
formatted_question: Where do the progenitor cells for bone fracture healing float around? (A) lymph system (B) digestive tract (C) Natural world (D) Moist habitats (E) properly stored (F) bone marrow (G) recyclable (H) biceps