Hint: The force on the dipole depends on the electric field.

Explanation: If the lines of force are equidistant and parallel straight lines, the field is uniform and if either lines of force are not equidistant, or straight line or both, the field will be non-uniform. The number of electric field lines passing per unit area is proportional to the strength of the electric field. For example, see the following figures:
                
Hence in a given question, from the given pattern of electric field lines, it is clear that the strength of the electric field decreases from left to right. As a result force on charges also decreases from left to right. Here in the given figure, the force on charge \(-q\) is greater than the force on charge \(+q\) in turn dipole will experience a force towards left.
Hence, option (3) is the correct answer.