The best example of a domain-specific language (DSL) from the options given seems to be "shape," as it suggests a specific area of focus related to geometric concepts or graphical representations. Domain-specific languages are tailored for specific application domains, so in contexts like geometry, design, or graphics, a DSL that focuses on shapes would be relevant.
If the other terms are provided in a specific context (like programming or graphics), they might also represent a DSL, but "shape" is the most straightforward as it indicates a specific concept within a particular domain.