A number of your employees are calling you stating that they are not able to access any of the external websites.

You try accessing google from your desktop and you are having problem in accessing google too. You know google website's IP address is $172\mathrm{.}217\mathrm{.}6\mathrm{.}46.$

When you enter this number in your browser and hit enter, you are able to access Google.

Which of the following is the most likely cause of the problem?

A TCP issue

A DNS issue

A DHCP issue

A NAT issue