According to the passage, if the price in the machine is too high, the cause(s) may be______.

A．a scanner
B．a telephone hookup
C．an adding machine
D．an employee

A．Migration of large numbers of people may cause conflict.
B．The newest arrivals can hardly get good jobs.
C．Native people often resent newest arrivals because they cannot communicate easily with the latter.
D．Usually it has taken several decades for each group of newest arrivals to be accepted into the mainstream of society in the host country.