Which statement best describes Protocol Buffers usage?

Which statement best describes Protocol Buffers usage?

• A. A binary serialization format used by gRPC to define service contracts.
• B. A text-based data interchange format used by REST.
• C. An API style that builds endpoints around actions.
• D. A schema language for GraphQL contracts.

Answer: (A)

Protocol Buffers encode data in a compact binary wire format and provide a schema for both the data structures and the services that operate on them. In gRPC, you describe your messages and your service RPCs in .proto files, and the tooling uses that schema to generate client and server stubs while serializing all calls as the binary protobuf payloads. This combination is why this statement is the best fit: it captures that Protocol Buffers are a binary serialization format used by gRPC to define service contracts. By contrast, REST typically uses text formats like JSON or XML, not the binary protobuf wire format; GraphQL relies on its own schema language rather than Protocol Buffers.

Protocol Buffers encode data in a compact binary wire format and provide a schema for both the data structures and the services that operate on them. In gRPC, you describe your messages and your service RPCs in .proto files, and the tooling uses that schema to generate client and server stubs while serializing all calls as the binary protobuf payloads. This combination is why this statement is the best fit: it captures that Protocol Buffers are a binary serialization format used by gRPC to define service contracts. By contrast, REST typically uses text formats like JSON or XML, not the binary protobuf wire format; GraphQL relies on its own schema language rather than Protocol Buffers.