The options control whether the maximum deformations are related to the shifted ends of members or sets of members (connection line between start and end nodes of the deformed system) or to the undeformed initial system. Generally, the deformations are designed relative to the displacements in the entire structural system.
An article of the Knowledge Base on our website presents an example describing the relation of deformations.
You can check and adjust, if necessary, the limit deformations in the National Annex Settings dialog box (see Figure 2.10).
In the serviceability limit state design of steel bridges, it is necessary to check the slenderness ratio of web plates in order to avoid excessive rippling of plates ("web breathing") as well as stiffness reductions due to plate buckling. The check box Design as steel bridge structure according to EN 1993-2, 7.4  allows you to analyze the breathing (repeated out-of-plane deformation), which can result in fatigue problems at the web-to-flange connections.
You have to specify if a Road bridge or a Railway bridge is designed because there are different criteria for each case.
With the two options you can decide in which of the local member axes a precamber ("rise"), if applicable, is available. Depending on the setting, column F of Window 1.9 shows wc,v or wc,u as title (see Figure 2.36).