Naturally the audiences that support various kinds of music are not identical.There are separate audiences，of widely differing tastes and musical receptivity，for opera，symphony and chamber music.The oratorio audience is a very special group made up of the most conservative tastes and opinions.One suspects that it is recruited largely from friends and families of the singers.Now a stage full of happy and earnest oratorio singers must represent considerable potential ticket sales，and，if this is true，it does not malt much difference what work the singers select to perform.Anyone who has ever sung in a chorus knows what fun it is to sing Handel.The music is easy to grasp，fits the voice well，and fine effects are achieved with a minimum of professional skill.The plan of the Handel oratorio is ideal for the ordinary amateur singing group.All the hard parts are taken by professional soloists，who can be imported for the occasion.Therefore the chorus can make a public appearance after long，leisurely preparation and add on at the last moment the final professional touches.Thus the never-ending vogue of the oratorio and its unchanging aspect must be attributed，at least partially，to the amateur choral societies that are to be found in almost every community.

What does the passage mainly discuss?（）

A．Oratorio performers and their audience.
B．Differences in music audiences.
C．The rise of amateur choral societies.
D．Community receptivity to music.