Which of these commands allows you to use shared libraries that are in /usr/local/lib?

Which of these commands allows you to use shared libraries that are in /usr/local/lib?

A.
export LD_PRELOAD=/usr/local/lib

B.
export LD_LIBRARY_PATH=/usr/local/lib

C.
ldconfig /usr/local/lib

D.
ldd /usr/local/lib