Two rods of different materials having coefficients of linear expansions ${\alpha }_1\text{ and }{\alpha }_2$ and Young moduli $Y_1\text{ and }{Y}_2$ are fixed between two rigid walls and heated by same temperature difference thermal stress developed in both rods is same, If ${\alpha }_1:{\alpha }_2=2:3,Y_1:Y_2$ is

• A

  2 : 3    

• B

  1 : 1    

• C

  3 : 2    

• D

  4  :  9