**Correct option is: C) 25**

First 5 odd multiples of 5 are

\(5 \times1, 5 \times3, 5\times5, 5\times7 \) and \(5\times9\)

or 5, 15, 25, 35, 45

\(\therefore\) Mean = \(\frac {sum }{Total \,No} = \frac {5 + 15 + 25 + 35 + 45}5 = \frac {125}5 = 25\)

\(\therefore\) Mean of first 5 odd multiples of 5 is 25.