单项选择题

A.(F/P,i,n)=(A/P,i,n)X(F/A,i,n)
B.(F/A,i,n)=(F/P,i,n)X(P/A,i,n)
C.(A/P,i,n)X(F/A,i,n)X(P/F,i,n)=l
D.(A/P,i,n)=(A/F,i,n)—i