Among the headquarters staff of a well-known multinational company, all those who understand English are not proficient in Indonesian, some are not proficient in Spanish, some are proficient in Korean, are proficient in Indonesian, all are proficient in Spanish, and some are proficient in Korean. English. If the above statement is true, which of the following must also be true? ? ['Some Korean-speaking employees are not proficient in Indonesian.', 'Some people who do n’t know Spanish well know Indonesian.', 'Some Korean-speaking workers are not proficient in English.', 'Some English speakers who are not proficient in Korean.']