Which command removes every o, l, and h character from the input hello labex?
o
l
h
hello labex
echo 'hello labex' | tr -s 'olh'
echo 'hello labex' | tr 'olh' 'OLH'
echo 'hello labex' | tr -d 'olh'
echo 'hello labex' | cut -d 'olh'