Outermost loop will run for $n$ times , will not effect $2^{nd}$ and $3^{rd}$ loop.
outermost loop will run for $n$times
$j=1\rightarrow k=1$
$j=2 \rightarrow k=1,2$
$j=4\rightarrow k=1,2,3,4$
$j=8\rightarrow k=1,2,3,4,5,6,7,8$
$\vdots \vdots$
$j=n\rightarrow k=1,2,3,4,5,6,7,8.....2^h$
k will run -:
3rd loop$=2^0+2^1+2^2+.....2^h$
$=2^{h+1}-1$
$2^h=n\Rightarrow h=\log n$
3rd loop$=2^{\log n +1}-1=n^{\log 2} \times 2-1\approx n$
Outermost loop will run $n$times
Overall time complexity=$\Theta (n^2)$