One Reason Movie Theatres Charge a Lower Admission Price to Senior

One reason movie theatres charge a lower admission price to senior citizens is that

A) movie-theatre owners are able to practice perfect price discrimination.
B) government sets the price policies.
C) senior citizens have a more elastic demand than other movie-goers.
D) senior citizens have a less elastic demand than other movie-goers.
E) senior citizens have a higher willingness-to-pay than other people.