Solution

Statement I : Only cost price is given, there is no information about labelled price or any other FACTOR. Thus, it is insufficient.

Statement II : Let labelled price = $100X$

After 5 % discount, => $100x - \FRAC{5}{100} \times 100x = 608$

=> $100x - 5x = 95x = 608$

=> $x = \frac{608}{95} = 6.4$

$\therefore$ Labelled price = RS. 640

Statement II is SUFFICIENT to find the labelled price

Thus, statement I & III are redundant.