Final answer:
The class of Biological Safety Cabinets (BSCs) without protection against plant pathogens is likely to be Class I, as it offers protection only against low to moderate risk biological agents and not against specific pathogens. The correct option is A.
Step-by-step explanation:
The question seems to be asking which class of Biological Safety Cabinets (BSCs) does not protect against plant pathogens. Biological Safety Cabinets are categorized into three classes: Class I, II, and III. Class I BSCs protect laboratory workers and the environment from exposure to low to moderate risk biological agents but do not necessarily protect against plant pathogens.
Class II and Class III BSCs are designed to provide protection for the material or devices in the cabinet as well as the personnel and the environment, with Class III BSCs being the most secure and used with high-risk biological agents.
Therefore, the class with no protection against plant pathogens is likely to be Class I, as the other classes are designed to handle more hazardous materials and contain any potential pathogens.