題目:設(shè)函數(shù)f(x)在[a,b]上連續(xù),在(a,b)內(nèi)可導(dǎo),且f′(x)>0,f(a)<0,f(b)>0,則根據(jù)零點定理,存在c∈(a,b)使得( )。A. f(c)=0B. f′(c)=0C. f(c)=f(a)D. f(c)=f(b)