An IPv4 address consists of how many bits?

Concept: An IP address is a fixed-length binary identifier assigned to a device on a network, and its length is defined by the IP protocol version in use — IPv4 defines this length as a constant, standardized in RFC 791, regardless of how the address is displayed (binary, decimal, or hex).

Application: For IPv4 specifically, the standard fixes the address at four segments (octets), each 8 bits wide, joined together to form the complete address. Multiplying the segment count by the bits per segment gives the total address length: 4 segments × 8 bits/segment = 32 bits. So an IPv4 address is 32 bits long, matching the option '32'.

Cross-check: This is consistent with the familiar dotted-decimal notation — an address such as 192.168.1.1 has four numbers, each capped at 255 (the largest value that fits in 8 bits), confirming 4 × 8 = 32 bits total. It also distinguishes IPv4 from IPv6, which instead uses a 128-bit address written as eight 16-bit groups — a newer, larger addressing standard designed to solve IPv4's address-exhaustion problem.

Result: Therefore, an IPv4 address consists of 32 bits.