Which of the following strategies will mitigate the risk of a zero-day vulnerability MOST efficiently?

A SaaS provider wants to maintain maximum availability for its service.
Which of the following should be implemented to attain the maximum SLA?

In an existing IaaS instance, it is required to deploy a single application that has different versions.
Which of the following should be recommended to meet this requirement?

A support engineer wants to prevent users from running malware on several IaaS compute instances. Which of the following will BEST achieve this objective?

A systems administrator wants to have near-real-time information on the volume of data being exchanged between an application server and its clients on the Internet.
Which of the following should the systems administrator implement to achieve this objective?