Answer: Option B
Let the thickness of the bottom be x cm
Then,
$$\left[ {\left( {330 - 10} \right) \times \left( {260 - 10} \right) \times \left( {110 - x} \right)} \right]$$       $$ = 8000 \times 1000$$
$$ \Rightarrow 320 \times 250 \times \left( {110 - x} \right) = $$       $$8000 \times 1000$$
$$\eqalign{
& \Rightarrow \left( {110 - x} \right) = \frac{{8000 \times 1000}}{{320 \times 250}} \cr
& \Rightarrow \left( {110 - x} \right) = 100 \cr
& \Rightarrow x = 10\,cm \cr
& \Rightarrow x = 1\,dm \cr} $$