Out of given four waves (1),(2),(3) and (4)
`y=asin(kx+omegat)` .(1)
`y=asin(omegat-kx)` ..(2)
`y=acos(kx+omegat)` ..(3)
`y=acos(omegat-kx)` .(4)
emitted by four different source `S_1`,`S_2`,`S_3` and `S_4` respectively, interference phenomena would be observed in space under appropriate conditions when
A. Source `S_(1)` emits wave (1) and `S_(2)` emits wave (2)
B. Source `S_(3)` emits wave (3) and `S_(4)` emits wave (4)
C. Source `S_(2)` emits wave (2) and `S_(4)` emits wave (4)
D. `S_(4)` emits waves (4) and `S_(3)` emits waves (3)
