Two wires $A$ and $B$ made of same material and having their lengths in the ratio $6 : 1$ are connected in series. The potential difference across the wires are $3\,V$ and $2\,V$ respectively. If $r_A$ and $r_B$ are the radii of $A$ and $B$ respectively, then $\frac{{{r_B}}}{{{r_A}}}$ is
  • A$\frac{1}{4}$
  • B$\frac{1}{2}$
  • C$1$
  • D$2$
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