Answer:
 c. 750 units
Step-by-step explanation:
The computation of the inventory position is shown below: 
Inventory position (IP) = Number on‐hand inventory + Number of scheduled receipts - number of backorders 
= 700 units + 150 units - 100 units 
= 750 units 
We simply added on hand inventory units, scheduled receipts units and deducted the back orders units so those correct units could find out