The MPEG standard is primarily a _____ specification?

Concept: MPEG (Moving Picture Experts Group) standards do not standardize how a video or audio encoder is built. The committee's actual deliverable is the syntax and semantics of the compressed data stream and the matching decoding process — in other words, the format of the bitstream — so that any compliant decoder can correctly interpret data produced by any compliant encoder.

Application: Applying this to the given item: the MPEG standard defines exactly how compressed audio/video data is organised into a stream of bits (frame headers, motion vectors, quantised coefficients, and so on) and how a decoder must interpret that stream. This bitstream syntax is the actual object that MPEG standardises, which is why the specification type described in the stem is a Bitstream specification.

Contrast: The other terms describe different, unrelated units of data:

• Unicodestream — Unicode is a character-encoding scheme that assigns a numeric code point to each text character; it concerns representing textual symbols, not how compressed audio/video data is structured.

• Bytestream — grouping data into 8-bit bytes is a general-purpose data-transport convention (for example, file I/O), not the specific syntax MPEG standardises for compressed media.

• Wordstream — grouping data into fixed-size processor words (for example, 32-bit) reflects hardware register width, not the compressed-media syntax that MPEG defines.

Hence, the MPEG standard is primarily a Bitstream specification.