What is the normal room air temperature?

The normal room air temperature is often understood to be around 70°F to 75°F, which is generally considered comfortable for indoor environments. However, in the context of refrigeration and industrial applications, the options given reflect temperatures closer to the cold environments typical of storage areas or walk-in coolers.

Among the provided options, 35°F is a temperature that is typically used in refrigeration settings. This temperature is above freezing, allowing for the effective storage of perishable goods while also minimizing spoilage and maintaining food safety. It is within the range used in many cold storage operations, particularly for items such as meat, dairy, and some fruits and vegetables.

The other temperatures listed (30°F and 40°F) can also be relevant in certain cold storage contexts, but 35°F is a commonly accepted target for maintaining a balance between preservation and potential freezing, making it the most appropriate answer in this scenario.