Step 1: Understanding the genre of the novel.
The Mistress of Spices by Chitra Divakaruni is known for its use of magical realism. It blends the real and the supernatural elements in a way that is characteristic of the genre of magic realism.
Step 2: Explanation of the options.
(A) The novel incorporates elements of magical realism, where the mystical world of spices and their powers is intertwined with the real world.
(B) While the novel does explore themes of immigration, it is not primarily classified as a novel about immigrant experience.
(C) It is not a science fiction novel, as it does not deal with futuristic or technological elements.
(D) The novel is not written in an epistolary form, where the narrative is delivered through letters.
Step 3: Conclusion.
The correct answer is (A), as the novel is primarily an experiment in magical realism.