Final answer:
The new painting will likely be unveiled at the exhibition, as it is a common practice for artists to reveal their work at such formal events.The correct option is C.
Step-by-step explanation:
The question 'When are you going to unveil your new painting?' is related to an exhibition where an artwork, such as a painting, is typically revealed to the public. Considering that you have recently completed a painting of a sunset and have referenced Gauguin's portrait, it seems like you are involved in an artistic process and community. The best answer to when the new painting will be unveiled would be option (c) - At the exhibition. This choice is most appropriate as it suggests a formal event where artists typically present their new work. Whereas, answer (a) seems too soon since you just finished your painting, (b) is not specific enough, and (d) suggests indecision which would not be typical in a planned event such as an exhibition.