Whether the tomato-ripening rooms installed by farmers is eligible is determined by_______________..

A．She will do it for the man.
B．The clerk is unable to do it.
C．She will tell the man how to use the machine.
D．She will tell the man how to find the clerk.

A．Where it is.
B．When it is open.
C．How she can go there.
D．What she can see there.