The number of Black & Bleu oysters served varies by restaurant; check the specific restaurant's menu for the correct quantity.
The question you're asking seems to be related to a menu item from a restaurant, which is specific to that business's offering. The number of oysters included in a serving of Black & Bleu oysters can vary by the restaurant, as there is no standard across all restaurants. To find the correct answer, you would need to check the menu of the specific restaurant you are asking about or their website if available. If you are referring to a question in a textbook or an exam, often such questions are hypothetical and would provide you with the necessary context to choose the correct answer from the options given (a) 4 (b) 6 (c) 8 (d) 10.