You are tasked to configure the DHCP server to lease the last 100 usable IP addresses in subnet to 10.1.4.0/23. Which of the following IP addresses could be teased as a result of the new configuration

Question

Options

• A210.1.55.200
• B10.1.4.254
• C10.1.5.200
• D10.1.4.156

• A
  8% (2)
• B
  4% (1)
• C
  84% (21)
• D
  4% (1)

Explanation

Explanation

Option C (10.1.5.200) is correct because the subnet 10.1.4.0/23 encompasses the range 10.1.4.0 – 10.1.5.255, with usable hosts from 10.1.4.1 to 10.1.5.254. The last 100 usable addresses count backwards from 10.1.5.254, giving a pool of 10.1.5.155 – 10.1.5.254, and 10.1.5.200 falls squarely within that range.

• Option A (210.1.55.200) is wrong because it belongs to a completely different network - not even close to the 10.1.x.x range.
• Option B (10.1.4.254) is in the correct network but sits in the first half of the subnet (10.1.4.x), far outside the last 100 addresses.
• Option D (10.1.4.156) is also in the first half of the subnet and is well outside the last 100 usable addresses.

Memory Tip: For a /23 subnet, remember it spans two consecutive /24 blocks (e.g., .4.0 and .5.0). The "last 100" addresses will always land in the second block (.5.x), so any answer pointing to the first block (.4.x) is automatically wrong.

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