The stress versus strain graphs for wires of two materials A and B are as shown in the figure. lf Y_A and Y_B are the Young's moduli of the materials, then

• A

  ${\mathrm{Y}}_{\mathrm{B}} = 2{\mathrm{Y}}_{\mathrm{A}}$

• B

  ${\mathrm{Y}}_{\mathrm{A}} = {\mathrm{Y}}_{\mathrm{B}}$

• C

  ${\mathrm{Y}}_{\mathrm{B}} = 3{\mathrm{Y}}_{\mathrm{A}}$

• D

  ${\mathrm{Y}}_{\mathrm{A}} = 3{\mathrm{Y}}_{\mathrm{B}}$