Which of the following instruments sounds as written with a range of C2 or A2 to C7?

The marimba is the correct answer as it is an instrument that sounds as written within the specified range of C2 or A2 to C7. The marimba has a wide range and is known for its rich, warm tone produced by the wooden bars that are struck with mallets. Its overall range allows it to cover both the lower and upper registers effectively.

In contrast, while the xylophone also has a wide range, it typically starts at a higher pitch, often around F3 and extends upwards, making its range slightly different from the one specified. The glockenspiel, known for its higher pitch and melodic capabilities, usually has a range that starts around G3 or higher, extending to C7, but does not cover the lower range indicated in the question. Cymbals, on the other hand, do not have a definite pitch and are primarily used for their percussive qualities rather than melodic purposes. Thus, the marimba stands out as the instrument that presents the range accurately as specified.