What translates source code into machine code one line at a time?

• A. Interpreter
• B. Compiler
• C. Assembler
• D. Linker

Answer: (A)

Translating source code into machine-ready instructions one line at a time describes an interpreter. An interpreter reads high-level code and processes it line by line, translating or executing each line as the program runs, which allows immediate execution without first producing a separate executable. This is different from a compiler, which analyzes the entire program and outputs standalone machine code before it runs. An assembler takes assembly language—closer to machine language—and converts it to machine code, typically one instruction at a time, but it’s translating a low-level representation rather than high-level source code. A linker merely combines multiple object files into a single program and does not perform translation.