According to the passage, _____is the key factor to making "Nowcasts" a reality.

A．Modern man makes every effort to participate in modern life.
B．Modern man can become more intelligent by receiving the best thoughts of the ablest mind through television.
C．Modern man likes to consume, but few produce.
D．Television makes modern man himself think less.

A．the computer is not used to forecast specific local events
B．the computers are not advanced enough to predict it
C．the weather data people collect are often wrong
D．weather conditions in some small regions are not available