Which preservative is specifically mentioned for use in Anthrax vaccines?

The correct choice is formaldehyde, as it is commonly used in the manufacturing process of various vaccines, including anthrax vaccines. Formaldehyde acts as a preservative and inactivating agent, facilitating the development of a safe and effective vaccine by ensuring that the viral or bacterial components are not infectious but still capable of provoking a robust immune response.

In the context of anthrax vaccines, formaldehyde plays a crucial role in inactivating the anthrax pathogen, allowing the vaccine to evoke an immune response without the risk of causing disease. This process is integral to the efficacy and safety of vaccines, ensuring they can be administered to individuals without adverse reactions related to the infectious agent.

The other options, while related to vaccine processes, do not serve as primary preservatives in anthrax vaccines. For instance, thimerosal has been used in some vaccines as a preservative but is not specifically mentioned for anthrax vaccines. Neomycin and streptomycin are antibiotics that can be used to prevent bacterial contamination during vaccine preparation but do not function as preservatives for the anthrax vaccine itself.