According to the speaker, how many singers are there in the band of the Beatles

A．Phenomenologists had a ball in 1964 with Beatlemania.
B．The Beatles had to cancel all one-night bookings because of riots.
C．An album "Meet the Beatles" with their single record was released.
D．Beatlemania, a generally harmless form of madness, came from Britain.

A．the different use of bicycling
B．the important use of bicycling
C．the influence of bicycling on economy
D．the part bicycling can play in economy