Final answer:
Pears can be safely processed in a boiling water canner, unlike low-acid foods such as carrots, pumpkin, and beets, which require a pressure canner to reach the necessary temperature of 116 °C (240 °F) for preventing botulism.
Step-by-step explanation:
Of the following foods—carrots, pears, pumpkin, and beets—which can be safely processed in a boiling water canner? The answer is B. Pears. Pears are a high-acid food, which allows them to be safely processed in a boiling water canner. Low-acid foods, such as carrots, pumpkin, and beets, require processing at temperatures higher than boiling, specifically at least 116 °C (240 °F), to kill Clostridium botulinum endospores. This temperature can only be reached using a pressure canner. Boiling water canners are not suitable for low-acid foods because they do not reach temperatures high enough to ensure safety from botulism. Therefore, for low-acid foods, pressure canning is the recommended preservation method. Additionally, it is recommended by the CDC to boil home-canned foods for approximately 10 minutes before consumption to ensure the deactivation of any botulinum toxin present.