Boolean Expression with Laws

Question

Hello can somebody help me? How this boolean expression simplified?

abcd + d

it simplified as:

d

im trying to use the Laws I don't understand at all

Here's the Laws

Basic Boolean Laws
Idempotent Law
    A * A = A
    A + A = A 
Associative Law
    (A * B) * C = A * (B * C)
    (A + B) + C = A + (B + C) 
Commutative Law
    A * B = B * A
    A + B = B + A 
Distributive Law
    A * (B + C) = A * B + A * C
    A + (B * C) = (A + B) * (A + C) 
Identity Law
    A * 0 = 0     A * 1 = A
    A + 1 = 1     A + 0 = A 
Complement Law
    A * ~A = 0
    A + ~A = 1 
Involution Law
    ~(~A) = A 
DeMorgan's Law
    ~(A * B) = ~A + ~B
    ~(A + B) = ~A * ~B 
Redundancy Laws
Absorption
    A + (A * B) = A
    A * (A + B) = A 

    (A * B) + (A * ~B) = A
    (A + B) * (A + ~B) = A 

    A + (~A * B) = A + B
    A * (~A + B) = A * B 

Thanks in advance!

Answer 1

It's indeed D, by the following:

abcd+d -> (a+d)*(b+d)*(c+d)*(d+d) // Distributive Law  
(a+d)*(b+d)*(c+d)*(d+d) -> (a+d)*(b+d)*(c+d)*d // Idempotent Law - d+d=d  
(a+d)*(b+d)*(c+d)*d -> (a+d)*(b+d)*d  // Redundancy Laws - (c+d)*d = d  
(a+d)*(b+d)*d -> (a+d)*d  // Redundancy Laws - (b+d)*d = d  
(a+d)*d -> d  // Redundancy Laws - (a+d)*d = d