Given set of scores= 125, 236, 334, 486, 564, 525, 625, 702

We know the formula,

 $\mathrm{Average} \left(\mathrm{A}\right)=\frac{\mathrm{Sum} \mathrm{of} \mathrm{given} \mathrm{values} \left(\mathrm{S}\right)}{\mathrm{Total} \mathrm{number} \mathrm{of} \mathrm{values} \left(\mathrm{N}\right)}$

 Here,

 Sum of given values(S)

=125+236+334+486+564+525+625+702

= 3597

Total number of values(N)= 8

Substituting these values we get (A),

 $= \frac{3597}{8}=449.625$

Hence, Option B is correct.