Botanist: It has long been believed that people with children or pets should keep poinsettia plants out of their homes. Although this belief has been encouraged by child-rearing books, which commonly list poinsettias as poisonous and ttherefore dangerous, it is mistaken. Our research has shown, conclusively, that poinsettias pose no risk to children or pets. Which one of the following most accurately expresses the conclusion drawn in the botanist's argument? ['According to many child-rearing books, poinsettias are dangerous.', 'Poinsettias are not dangerously poisonous.', 'The belief that households with children or pets should not have poinsettias is mistaken.', 'Poinsettias pose no risk to children or pets.']