i) is cfl,but not dcfl,since there is non determinism (by seeing b,when top of stack is a, you can either pop it or dont do anything and wait for c and pop one a for every c and if by the end all a's are popped for every c u can accept it or if all a's are pooped and sill c's remain.
ii)clearly csl.
iii)cfl but again not dcfl, as u can match either a's and b's or you can see whether no of a's <> no of c's(for each c pop one a, if at the end atleast one a remain on tos and i/p string in empty or all a's are popped off still at least one c remain on tos u can accept it.)
iv) regular language (a*b*c*)
so option i,iii) & iv)
