You maintain a Power BI model with a fact table named 'Inventory' that records the on-hand quantity for each product at the end of each day, related to a marked Date table. The business wants a measure named 'Month-End Stock' that, when a month is selected in a matrix, shows the on-hand quantity as of the last date in that month that actually has data — not a sum across all days. Which DAX definition produces the correct semi-additive result?