How many usable host addresses are available in a /28 subnet?

Correct answer: 14

Option A is correct because a /28 subnet has 4 host bits, yielding 2 to the power of 4 equals 16 total addresses, minus 2 for the network address and broadcast address, leaving 14 usable host addresses. Option B is incorrect because 8 usable hosts corresponds to a /29 subnet, which has 3 host bits giving 8 total addresses and only 6 usable hosts. Option C is incorrect because 30 usable hosts corresponds to a /27 subnet with 5 host bits, not a /28. Option D is incorrect because 16 is the total number of addresses in a /28 block including the network and broadcast addresses, not the usable host count.