Which statement about UTF-8 is accurate?

Which statement about UTF-8 is accurate?

• A. It uses a variable-length encoding and is backward compatible with ASCII.
• B. It uses fixed-length 4 bytes for all characters.
• C. It cannot represent non-Latin scripts.
• D. It is no longer used on the web.

Answer: (A)

UTF-8 encodes Unicode using a variable-length scheme, with characters taking 1 to 4 bytes. The first 128 code points match ASCII exactly, so any ASCII text is valid UTF-8 without changes. This backward compatibility is a major reason UTF-8 is so widely adopted, since existing ASCII data and tools continue to work while still allowing the full Unicode set. Not all characters require 4 bytes—many common characters use 1 or 2 bytes, and some use 3 bytes—so UTF-8 is efficient for many scripts. Because it can encode the entire Unicode range, it supports non-Latin scripts, symbols, and emoji. It is still the dominant encoding on the web today, so the idea that it’s no longer used is incorrect. A fixed-length 4-byte approach would not accommodate the full range of characters efficiently or at all for ASCII.

UTF-8 encodes Unicode using a variable-length scheme, with characters taking 1 to 4 bytes. The first 128 code points match ASCII exactly, so any ASCII text is valid UTF-8 without changes. This backward compatibility is a major reason UTF-8 is so widely adopted, since existing ASCII data and tools continue to work while still allowing the full Unicode set. Not all characters require 4 bytes—many common characters use 1 or 2 bytes, and some use 3 bytes—so UTF-8 is efficient for many scripts. Because it can encode the entire Unicode range, it supports non-Latin scripts, symbols, and emoji. It is still the dominant encoding on the web today, so the idea that it’s no longer used is incorrect. A fixed-length 4-byte approach would not accommodate the full range of characters efficiently or at all for ASCII.