user: Question: What is the origin when the destination is Mumbai?
Columns: ['Sl. No.', 'Train number', 'Train name', 'Origin', 'Destination', 'Time', 'Service', 'Route/Via.']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 16724.0, 'Ananthapuri Express', 'Trivandrum', 'Chennai', '17:15', 'Daily', 'Nagercoil,Madurai,Tiruchi']
SQL:

assistant: SELECT "Origin" FROM "Table" WHERE "Destination" = 'Mumbai';