Correct Answer - 1

Number of unpaired electron are given by Magnetic moment `=sqrt([n(n+2)])` where `n` is number of unpaired electrons or `1.73=sqrt([n(n+2)])` or `1.73xx1.73=n^(2)+2n`

`:. n=1`

Now vanadium atom must have one unpaired unpaired electron and thus its confiuration is:

`_(23)V^(4+): 1s^(2) 2s^(2) 2p^(6)3s^(2)3p^(6) 3d^(1)`