Sandra is creating a new passcode for her phone. Her passcode will be 5 digits and she can choose any number between 0-9, with no repetition allowed. How many possible options passcode does she have?
 a. 10X10X10X10X10
 b.9X8X7X6X5
 c.5X4X3X2X1
 d.10X9X8X7X6