The LCD will be (bcd)^2.
For each factor in the denominators, you'll have a corresponding factor in the LCD.
Edit... Apparently, we aren't adding fractions...
b c d
__ x __ x ___
2 2 2
cd bd bc
I seriously do not understand fractions !
When I view this is looks wieird, it is b over cd squared times c over bd squared times d over bc squared. How do I find a common denominator with variables?