The occupations of Xiao Zhou, Xiao Wu, Xiao Deng, and Xiao Wang are: dancer, nurse, teacher and costume designer. Also know: Xiao Zhou has a higher salary than a nurse, Xiao Zheng has a lower salary than Xiao Wu, dancer The salary is lower than that of a costume designer. The costume designer is either Xiao Zheng or Xiao Wang. Based on the above statement, which of the following is true? ['The occupations of four people can be determined.', 'Only three of the four occupations can be determined.', 'Occupation of only two of four people can be determined.', 'Occupations of four people are uncertain.']