Practice quiz

A+ Networking Basics Quiz

Scenario-based original review questions about IP settings, DHCP, DNS, gateways, APIPA, Wi-Fi, and support commands.

Original review questions for learning and self-checking. These are not real exam questions.

Easy

1. A laptop shows IP address 169.254.44.21 with no default gateway. Other devices on the same Wi-Fi work. What is the best first focus?

A. The laptop Wi-Fi profile, adapter, or DHCP renewal path

B. The public website being visited

C. One application proxy setting

D. The default printer setting

Show answer

Correct answer: A. The laptop Wi-Fi profile, adapter, or DHCP renewal path.

Explanation: APIPA on one device suggests that endpoint did not get DHCP. The other options do not explain missing IP settings on one laptop.

Easy

2. A user can open websites by IP address but not by name. Which area should you check first?

A. DNS resolution

B. Default gateway hardware replacement

C. Printer queue

D. VPN client reinstall first

Show answer

Correct answer: A. DNS resolution.

Explanation: IP connectivity works, but name resolution fails. Hardware and printer checks do not match the symptom.

Medium

3. A desktop has IP 192.168.10.55, subnet mask 255.255.255.0, and no default gateway. It can reach a local printer but not the internet. What is most likely missing?

A. Default gateway

B. DNS suffix only

C. A different subnet mask with no gateway

D. A printer driver

Show answer

Correct answer: A. Default gateway.

Explanation: Local access can work without a gateway, but internet access needs a route out. DNS suffix, subnet-only changes, or printer drivers do not replace the missing gateway.

Medium

4. An Ethernet link light is on, but the PC has no valid IP address. Which result would best support a DHCP problem?

A. ipconfig shows 169.254.x.x

B. The DNS suffix is missing

C. The user has many browser bookmarks

D. The browser cache is full

Show answer

Correct answer: A. ipconfig shows 169.254.x.x.

Explanation: An APIPA address means Windows did not receive DHCP. The other facts do not explain missing IP configuration.

Medium

5. A teacher says classroom Wi-Fi is connected but the internet does not work. Three nearby laptops have the same issue. What is the best next step?

A. Check the access point, SSID/VLAN, DHCP, or upstream network path

B. Replace all three laptops immediately

C. Clear one browser cache only

D. Reinstall one browser only

Show answer

Correct answer: A. Check the access point, SSID/VLAN, DHCP, or upstream network path.

Explanation: Multiple devices in one area suggest shared network infrastructure. Replacing laptops or changing local cosmetic settings is premature.

Medium

6. A user reports slow Wi-Fi only in one corner of a room. Ethernet works normally at the same desk. What is the best first theory?

A. Wireless coverage or interference issue

B. DHCP server is completely down for everyone

C. The SSD is failing

D. The user account is locked

Show answer

Correct answer: A. Wireless coverage or interference issue.

Explanation: The wired network works and the issue is location-specific, so Wi-Fi signal or interference is more likely than DHCP, storage, or account problems.

Medium

7. A laptop has valid IP settings and can ping the gateway, but cannot open internal sites by name. Which command gives the most useful next clue?

A. nslookup internal site name

B. chkdsk /f

C. shutdown /s /t 0

D. sfc /scannow

Show answer

Correct answer: A. nslookup internal site name.

Explanation: The symptom points toward DNS. Disk, shutdown, and system file commands do not test name resolution.

Medium

8. A PC is set to static IP 192.168.20.50/24 with gateway 192.168.10.1. Other PCs in its area use 192.168.20.1 as gateway. What is the best correction?

A. Use the gateway that matches the local subnet, likely 192.168.20.1

B. Disable the network adapter permanently

C. Change DNS only

D. Reinstall the printer driver

Show answer

Correct answer: A. Use the gateway that matches the local subnet, likely 192.168.20.1.

Explanation: The gateway should normally be reachable in the local subnet. The other options do not address wrong static IP settings.

Hard

9. After a new access point install, clients connect to the SSID but get APIPA addresses. Wired clients on the same switch work. What is the strongest suspect?

A. SSID-to-VLAN or switch trunk configuration for the AP

B. Every client has a bad CPU

C. The website is offline

D. The printer driver is old

Show answer

Correct answer: A. SSID-to-VLAN or switch trunk configuration for the AP.

Explanation: Wireless association works but DHCP does not reach clients, often due to VLAN/uplink mismatch. CPU, website, and printer drivers do not fit.

Hard

10. A user says the network is down. Your checks show IP settings are valid, gateway ping works, DNS works, and only one cloud app fails. What is the best next action?

A. Check the app/service status, permissions, or app-specific issue instead of treating it as a general network outage

B. Replace the router immediately

C. Change DHCP scope for everyone

D. Factory reset the access point

Show answer

Correct answer: A. Check the app/service status, permissions, or app-specific issue instead of treating it as a general network outage.

Explanation: Layered tests show the general network path works. Broad network changes are risky and unsupported by the evidence.

Keep learning with the blog

Use the notes for deeper explanations and real support examples behind these questions.

Read notes