Roundworms may be free-living or parasitic, and dogs remain susceptible to reinfection with hookworms and roundworms. Given these facts, dogs remain what to free-living or parasitic species among the following options:
- hungry for
 - warm-blooded
 - susceptible
 - fertile
 - taken over by
 - more abundant
 - Animal survival
 - friendly towards


 

   susceptible      