In IPv4 addressing, what is the default address class of the IP address 195.152.12.1 based on its first octet?

Introduction / Context:
Classful IPv4 addressing is a traditional way of categorizing IP addresses based on the range of the first octet. Even though modern networks use classless addressing with CIDR, classful concepts are still tested in interviews and exams. This question asks you to identify the default class type of a specific IPv4 address, 195.152.12.1, by looking at its first octet.

Given Data / Assumptions:

• The address under consideration is 195.152.12.1.
• We use traditional classful IPv4 ranges based on the first octet.
• Class A addresses use first octets 1–126.
• Class B addresses use first octets 128–191.
• Class C addresses use first octets 192–223.

Concept / Approach:
To determine the class of an IPv4 address in the classful scheme, you examine the value of the first octet. Each class corresponds to a specific numeric range. The address 195.152.12.1 has a first octet of 195. This value is greater than or equal to 192 and less than or equal to 223, which places it in the Class C range by definition. Therefore, the address is a Class C address when using default classful rules.

Step-by-Step Solution:
1. Extract the first octet from the IP address 195.152.12.1; this is 195.2. Recall the classful boundaries: Class A is 1–126, Class B is 128–191, Class C is 192–223, Class D is 224–239, and Class E is 240–255.3. Compare 195 to these ranges: it is not in 1–126 and not in 128–191.4. Because 195 falls between 192 and 223 inclusive, it belongs to the Class C range.5. Option A correctly states that the address is Class C and explains that the first octet 195 lies between 192 and 223.6. Options B, C, and D deliberately mis-state the ranges and are incorrect.7. Therefore, the correct default class type is Class C.

Verification / Alternative check:
You can verify the class ranges by consulting standard networking references or IP addressing tables. Another check is to remember that Class C networks were historically used for smaller networks with many networks and fewer hosts per network, typically using a default subnet mask of 255.255.255.0. Addresses beginning with 195 commonly appear with such masks, supporting the conclusion that the address is Class C.

Why Other Options Are Wrong:
Option B is wrong because it mislabels the 1–126 range, which actually corresponds to Class A, not Class C.Option C is wrong because it mislabels the 128–191 range, which is Class B, not Class C.Option D is wrong because the 224–239 range is Class D, reserved for multicast, and is not referred to as Class C.

Common Pitfalls:
Students sometimes mix up the numeric boundaries of the classes or forget that 127 is reserved for loopback and not part of the standard Class A network range. Another common mistake is to think that class type directly controls modern subnetting, whereas CIDR allows more flexible masks. For exam questions, however, sticking to the historical class ranges is usually sufficient to determine the correct class.

Final Answer:
Class C, because the first octet 195 lies between 192 and 223.