Define "source language" in the context of interpreting.

The term "source language" in the context of interpreting refers specifically to the language that is being spoken or signed from which the interpretation is provided. This is critical in the interpreting process as it is the language that the interpreter listens to or observes and then translates into another language, known as the target language. Having a clear understanding of the source language allows the interpreter to accurately convey the message, tone, and nuances to the target audience.

Recognizing this definition helps in clarifying the role of the interpreter in bridging language barriers and ensures effective communication. The other options do not correctly capture the essence of what a source language is, either referring to written materials, the interpreter's primary language, or a language's level of comprehension among participants, which detracts from the focus on the interpretable spoken or signed language itself.