SQL Data Analyst — Hard Which window function calculates a running total of sales ordered by date within each region? A SUM(sales) OVER (PARTITION BY region ORDER BY sale_date) B SUM(sales) OVER (ORDER BY sale_date PARTITION BY region RANGE UNBOUNDED) C CUMSUM(sales) OVER (PARTITION BY region ORDER BY sale_date) D SUM(sales) OVER (PARTITION BY region ORDER BY sale_date ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) Show explanation
