Write SQL query to solve given problem: Indicate the patient's full name with the lowest body mass index in kg/m2.. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT T1.first, T1.last FROM patients AS T1 INNER JOIN observations AS T2 ON T1.patient = T2.PATIENT WHERE T2.DESCRIPTION = 'Body Mass Index' AND T2.UNITS = 'kg/m2' ORDER BY T2.VALUE LIMIT 1