To determine where the digit 8 belongs when you multiply the two red digits, we need to examine the multiplication of the digits in the positions A and B, which are 7 and 5 respectively.
So, the multiplication is:
\[ 7 \times 5 = 35 \]
The result of this multiplication is 35, which contains the digit 8. However, 35 does not inherently include the digit 8.
To satisfy the requirement of where the 8 would fit, we notice that if we hypothetically calculated the multiplication again or performed a different operation involving the positions, there wouldn't be a direct place for 8 that follows the multiplication of these two digits.
Consequently, if your intention is to find a placement for an 8 directly resulting from the digits mentioned (7 and 5), based on our calculation, there isn't a logical position for the 8 based on the results of that multiplication (7 x 5) between the digits in positions A and B.
If you have a specific scenario or arrangement in mind regarding A, B, C, or D where we can place 8 based on other constraints, please clarify so I can assist further accordingly.