下列函数在定义域内连续的是
A. $f(x)=\ln x+\sin x$
B. $f(x)= \begin{cases}\sin x, & x \leq 0 \\ \cos x, & x>0\end{cases}$
C. $f(x)= \begin{cases}x+1, & x < 0 \\ 0, & x=0 \\ x-1, & x>0\end{cases}$
D. $f(x)=\left\{\begin{array}{cc}\frac{1}{\sqrt{|x|}}, & x \neq 0 \\ 0, & x=0\end{array}\right.$