In an interview, Max was asked to tell one difference between a software firewall and a virtual firewall. How should Max answer?

a. Software firewalls are locally installed on a device, whereas virtual firewalls run in the cloud.
b. Virtual firewalls are cost-free, whereas software firewalls are paid services.
c. Software firewalls can protect all the endpoints in a network, whereas virtual firewalls can protect only one device.
d. Virtual firewalls are used on almost all devices, whereas software firewalls are mostly used by enterprises.