Given,

${\mathrm{n}}_1=5, {\mathrm{n}}_2=10, {\mathrm{n}}_3=15, {\mathrm{a}}_1=25, {\mathrm{a}}_2=50, {\mathrm{a}}_3=35$

According to the formula,

Average price=$\frac{{\mathrm{n}}_1{\mathrm{a}}_1+{\mathrm{n}}_2{\mathrm{a}}_2+{\mathrm{n}}_3{\mathrm{a}}_3}{{\mathrm{n}}_1+{\mathrm{n}}_2+{\mathrm{n}}_3}$

$$\begin{gathered} =\frac{5\times 25+10\times 50+15\times 35}{5+10+15} \\ =\frac{25+100+105}{1+2+3} \\ =\frac{230}{6} \end{gathered}$$

= 38.33

Hence, Option C is correct.