"C" stands for "Compulsory exercises" and "O" stands for "Optional exercises".
s iː WORD_BOUNDARY s t æ n d z WORD_BOUNDARY f ɔ ɹ WORD_BOUNDARY k ə m p ʌ l s ə ɹ ɹ i WORD_BOUNDARY ɛ k s ə ɹ s aɪ z ɪ z WORD_BOUNDARY æ n d WORD_BOUNDARY oʊ WORD_BOUNDARY s t æ n d z WORD_BOUNDARY f ɔ ɹ WORD_BOUNDARY ɑ p ʃ ə n ə l WORD_BOUNDARY ɛ k s ə ɹ s aɪ z ɪ z WORD_BOUNDARY