There are five digits 1,2,3,4 and 5.Every digit can be selected any number of times.Hence we can select first digit 5 times.The second digit 5 times and the third digit 5 times.
Hence the number of ways in which the selection of three digits can be made
$\Rightarrow 5\times 5\times 5$ ways
$\Rightarrow 125$ ways
Hence (B) is the correct answer.