Janet saw on the news that a family of seven perished in a house fire—it was also revealed that the house did not have smoke detectors

As a result, she developed a persuasive speech stating that such tragedy can be avoided with the simple installation of a smoke detector in everyone's house. Janet was using which kind of proposition as her central idea?
a. proposition of value
b. proposition of fact
c. proposition of policy
d. proposition of action

b