ABC Companys management is considering to invest one million dollars to enhance security. The three topics are: (I) Purchase new fire wall, which increases P by 10 minutes, (II) Upgrade instruction detection system, which decreases D by 12 minutes, and (III) Invest new methods to respond to incidents, which decrease C by 30 minutes. Which is the most cost-effective choice?

a.

Option I

b.

Option III

c.

Option II

d.

None of the listed