Which of the following problems occur?

[answerhappygod]

i) Does a given program ever produce an output?
ii) If L is a CFL, then is L’ is also context-free?
iii) L’ is regular only if L is regular?
iv) If L is a recursive language, then, L’ is also recursive?
a) i, ii, iii, iv
b) i, ii
c) ii, iii, iv
d) iii, iv