IP address and DNS basics – UGC NET Question

Statements A, B and C correctly express how addressing and DNS work on the Internet, while statement D is incorrect. IP addresses identify devices, DNS maps domain names to these addresses, and IPv4 notation uses dotted decimal format. Encryption of e-mail depends on separate security protocols and configurations, not on DNS itself. Therefore, the set of correct statements consists of A, B and C only.

Option A:
Option A is incomplete because it includes only A and B and omits C. While A and B capture addressing and name resolution, C adds the important detail of common IPv4 notation. Excluding C means the combination does not include all correct statements.

Option B:
Option B is incorrect because it accepts D along with A and B. Although A and B are true, D overstates the role of DNS by attributing end-to-end encryption to it, which is not its function. Including a false statement invalidates this option.

Option C:
Option C is incorrect because it takes B and C as correct but leaves out A. A explains the basic purpose of an IP address and is fundamental to understanding the topic, so its omission makes the answer incomplete.

Option D:
Option D is correct because it groups A, B and C, the three true statements, and excludes D, which confuses name resolution with security. This combination accurately reflects networking basics relevant for ICT.