The choices of this question are:
a. work-in-process inventory.
b. materials inventory.
c. partially-controlled inventory.
d. finished-goods inventory.
e. ready for sale.
I think the answer is a. work-in-process inventory. The materials are partially done and, in this case, the strings and inner sole are yet to be put on to the shoes. There might be other more processes where the shoes could go and finally be set a finish product.