单项选择题

设f(x)在[0,1]上连续,又

(A) F(x+π)>F(Ⅳ)(x∈(-∞,+∞)).
(B) F(x+π)<F(x)(x∈(-∞,+∞)).
(C) F(x+π)=F(x)(x∈(-∞,+∞)).
(D) x>0时F(x+π)>F(x),x<0 时F(x+π)<F(x).