The value of (P-a) * (P-b) * (P-c)………….* (P-z) is ____________

If the question would have been "can be" , then all the options would have been correct but since it has been given as 'is' , only option d satisfies.
Option A: The polynomial can start with any power of P. The order of powers of P does not make any difference. 
Option B:It is possible only when P = a or b or c ...... or z
Option C:The polynomial can start with any power of P. The order of powers of P does not make any difference.
Option D:This is true in all the cases.