Is Component 4 (Speaking and Listening Test) compulsory?

The Speaking and Listening component for syllabus 0500/0990 is optional and is separately endorsed on a scale of 1 (High) to 5 (Low). It is separately certificated from the main grade which is awarded on the standard Cambridge IGCSE grade scale of A* to U for 0500 and 9-1 for 0990.