In the 1908 Olympic games, the Olympic Marathon was lengthened from 40 km to approximately 42 km. Of the following which is the closer to the increase in the distance of the Olympic Marathon in miles ? (1 mile is approximately 1.6 km)

Question

$\begin{array}{1 1} (a)\;1.00 \\ (b)\; 1.25 \\ (c)\; 1.50 \\ (d)\; 1.75 \end{array}$