Answer: Option B
$$\eqalign{
& \pi {r^2} = 3850 \cr
& \Rightarrow {r^2} = \left( {\frac{{3850 \times 7}}{{22}}} \right) = 1225 \cr
& \Rightarrow r = 35 \cr
& {\text{Now, }}r = 35{\text{ cm, }}h = 84{\text{ cm}} \cr
& {\text{So,}} \cr
& l = \sqrt {{{\left( {35} \right)}^2} + {{\left( {84} \right)}^2}} \cr
& \Rightarrow l = \sqrt {1225 + 7056} \cr
& \Rightarrow l = \sqrt {8281} \cr
& \Rightarrow l = 91{\text{ cm}} \cr} $$
∴ Curved surface area :
$$\eqalign{
& = \left( {\frac{{22}}{7} \times 35 \times 91} \right){\text{ c}}{{\text{m}}^2} \cr
& = 10010{\text{ c}}{{\text{m}}^2} \cr} $$