Write a number sentence for the model. let one white tile equal +1 and one black tile equal –1.
a. –14 – (–6) = –8
b. 14 – 6 = 8
c. –14 – 6 = –8
d. –14 – (–6) = 8

The correct answer to this question is A. –14 – (–6) = –8. Based on the illustration attached, there are 14 black tiles in the first lane, white tile has 6, and equals to 8 black tiles. Since black tile is -1, then it will be -14. Thank you for posting your question. I hope that this answer helped you. Let me know if you need more help. 

The 3rd option/graph is correct.