Answer
$C)~91.0cm$
Work Step by Step
We can find the required focal length as
$f_{fluid}=[\frac{(n_{lens}-1)n_{fluid}}{n_{lens}-n_{fluid}}]f_{air}$
We plug in the known values to obtain:
$f_{fluid}=[\frac{(1.52-1)(1.33)}{1.52-1.33}](25.0)=91.0cm$
