IF cells in a range are empty, reference values in another cell range

The OFFSET is required to filter against different variables in other circumstances.

Correction, answer = 3. Rows 11, 12, 13 where:

Row 11: Variable = "X", Test 2 result = empty, therefore this row specifically relies on the empty cell condition, where Test 2 is empty, the formula needs to alternatively revert to test the result in the Test 1 range which in this instance contains the required “A” result
Row 12: Variable = "X" / Test 2 result = "A"
Row 13: Variable = "X" / Test 2 result = "A"

Rows that don't meet the criteria:
Row 14: Variable = "X" / Test 2 result = empty / Test 1 result = "B"
Row 15: Variable = "C" / Test 2 result = "A"
Row 16: Variable = "X" / Test 2 result = "C"