Which instrument is primarily associated with the Andean region and is played by blowing across holes?

The siku, also known as panpipes, is a traditional wind instrument associated with the Andean region. It consists of a series of tubes or pipes of varying lengths, which are typically made from bamboo or other materials. The player blows across the open ends of the pipes to produce sound, with each pipe producing a different pitch depending on its length. This method of sound production by using air creates a melodious and harmonically rich sound that is characteristic of the Andean musical tradition.

In contrast, the teponaztli is a slit drum common in Mesoamerican cultures and does not involve blowing across holes. The conch is a shell that can be used as a wind instrument, but it is not primarily associated with the Andean region like the siku. Mariachi refers more to a musical style and ensemble from Mexico that typically features a variety of string instruments and vocals, rather than a specific wind instrument from the Andes. Thus, the siku is the correct choice as it uniquely represents the method and cultural association described in the question.