c
\(\theta < C\)

\(\theta = 60\)

\(60 > C \Rightarrow \sin 60 > \sin C\)

\( \Rightarrow \frac{{\sqrt 3 }}{2} > \frac{{{\mu _{Liquid}}}}{{{\mu _{Prism}}}} \Rightarrow {\mu _{Liquid}} < \frac{{\sqrt 3 }}{2} \times {\mu _{Prism}}\)

\( \Rightarrow {\mu _{Liquid}} < \frac{{\sqrt 3 }}{2} \times 1.5 \Rightarrow {\mu _{Liquid}} < 1.3\).