Step 1: Concept:
Match each aim in the options to the body it belongs to. The passage gives one clear role for each body, so we can pair them.
Step 2: Pairing the roles:
ISO: develops standardisation and cooperation in the world. WTO: keeps trade running smoothly through agreements and settling disputes. HACCP: looks at each step of food handling for hazards. CAC: publishes the food standards document that protects consumers and keeps food trade fair.
Step 3: Read the options with these pairs:
Option 1 is the ISO role. Option 3 is the WTO role. Option 4 is a small outcome tied to hazard control and labelling, which is not the wide aim of a standards body. Option 2 states the Codex role in full.
Step 4: Confirm with the passage:
The passage says the CAC document protects consumers and ensures fair practices in food trade. Option 2 repeats both ideas (health protection and trade facilitation). No other option carries both.
Step 5: Conclusion:
Because only option 2 fits the Codex role fully, it is the answer.
Final Answer:
Option 2 is correct because it combines consumer health protection with fair food trade.
\[ \boxed{2} \]