Final answer:
The nursing student's effective learning statement is, "The agent is probably mustard gas, which causes skin burns and smells like garlic." Mustard gas matches the symptoms described by the nursing instructor.
Step-by-step explanation:
The nursing student's effective learning statement is, "The agent is probably mustard gas, which causes skin burns and smells like garlic."
Mustard gas is a chemical agent of terrorism that can cause severe skin burns and blisters, and it does have a garlic-like odor. In the situation described by the nursing instructor, the symptoms of burned or blistered skin, along with the garlic-like odor, are consistent with mustard gas exposure.
Other options mentioned, such as sarin gas, chlorine gas, and cyanide gas, do not match the specific symptoms described by the nursing instructor. Sarin gas, for example, is odorless and would not cause skin irritation. Chlorine gas causes respiratory symptoms but not skin burns. Cyanide gas does not have a garlic-like odor and would not cause skin discoloration.