In the following reaction sequence, correct structure(s) of Y is (are)

 

TsCl doesn’t affect the stereochemistry while other two reactions are ${\mathrm{S}}_{\mathrm{N}}2$ and hence invert the configuration twice which leads to retention of configuration. As the product if optically inactive, both (1) & (3) are the same and should give the product. (To avoid any confusion think of cyclohexane chair form i.e axial and equatorial forms)