Which type of fitting is used to make a 90-degree turn in a conduit run?

An elbow fitting is specifically designed to create a 90-degree turn in a conduit run. This type of fitting allows for changes in direction while maintaining the structural integrity of the conduit system. By utilizing an elbow, electricians can efficiently reroute conduits around obstacles or align them with junction boxes or other components. The design of an elbow facilitates a smooth transition, reducing potential stress on the conduit and minimizing the risk of damage from tight bends that could occur if other types of fittings were used.

The other options serve different functions: a coupling is used to connect two lengths of conduit in a straight line, a tee fitting creates a branch out of a main conduit run, and a connector typically connects conduit to an electrical device or junction box. None of these alternatives are suited for achieving a 90-degree angle.