OSPF (Open Shortest Path First) establishes router adjacencies and performs the DR/BDR (Designated Router/Broadcast Designated Router) election process in network types where multiple routers are connected to a common segment. The network type where OSPF will establish router adjacencies but will not perform the DR/BDR election process is:

A) Point-to-point

In point-to-point networks, there are only two routers directly connected to each other, so there's no need for a DR/BDR election because there are no multiple routers contending for control of the segment. OSPF routers in point-to-point networks will form adjacencies directly without the need for a DR and BDR.