Answer:
c. 5
Step-by-step explanation:
Counting the check digit, there are 12 digits, so this is a GTIN-12 code. Alternate digits are multiplied by 3 and the result summed with the sum of the other digits. The check digit is the amount required to make this sum be a multiple of 10.
(4 +9 +0 +0 +7 +2)·3 +(8 +0 +0 +3 +8) = 66+19 = 85
The check digit is 5, the number that must be added to this to make the total 90, a multiple of 10.
