Fishing activities in Bihar also involve:

Fish processing and drying
Boat building and repair
Net making
All of the above

The correct answer is: d) All of the above.

Fishing activities in Bihar involve a variety of tasks, including fish processing and drying, boat building and repair, and net making.

Fish processing and drying is the process of preparing fish for storage and consumption. This may involve filleting the fish, removing the skin and bones, and then drying the fish in the sun or by smoking.

Boat building and repair is the process of constructing and maintaining boats. This may involve carpentry, metalworking, and other skills.

Net making is the process of making nets for fishing. This may involve weaving, knotting, and other skills.

All of these tasks are essential to the fishing industry in Bihar.