An industrial union: is most concerned with increasing the demand for workers in an industry restricts supply of labor through licensing requirements organizes a wide range of workers in an industry to gain bargaining power is most effective in a purely competitive industry

I think the correct answer is the third option. An industrial union organizes a wide range of skilled and unskilled workers in an industry. It is a group where all workers regardless of position of a particular industry are to be members. These are organized in order to gain a bargaining power especially in strike events.