Lighting system of billboard changes seasonally, which is remote-control.

A．When the economy of those countries is not doing well.
B．At a later stage for investment in those countries.
C．When an unfavorable depreciation in allowance is used.
D．When the property of the plant is written off at a lower rate in the later years.

A．Tax rates differ greatly because of a tax holiday.
B．During a tax holiday, government doesn't levy taxes.
C．During a tax holiday, some of new subsidiaries will reduce taxes on machinery.
D．Problem of unemployment can be solved.