The correct answer is b) Frozen fish.
Fish processing industries in Kerala mainly produce frozen fish. This is because Kerala has a long coastline and a large fishing industry. The state also has a cold storage facility that can store frozen fish for long periods of time. Frozen fish is a popular export item from Kerala and is also sold in the domestic market.
Fresh fish is also produced by fish processing industries in Kerala. However, fresh fish is a perishable item and has a shorter shelf life than frozen fish. Therefore, it is not as popular as frozen fish.
Canned fish is not a major product of fish processing industries in Kerala. This is because canned fish is not as popular as frozen fish in the domestic market. Canned fish is also more expensive than frozen fish.
Fish oil is a byproduct of fish processing industries in Kerala. It is used in the production of animal feed and cosmetics. Fish oil is also used as a dietary supplement.
In conclusion, the correct answer is b) Frozen fish.