A certain college will continue to implement the overseas funding plan this year. It is proposed that six teachers, namely Teacher Liu, Teacher Zhang, Teacher Wang, Teacher Ma, Teacher Niu, and Teacher Zhou, will be sent to study abroad. Due to the funding, academic development needs of the college, courses There are many factors such as the arrangement of each person's visit to the school and the time of the visit. The selection must meet the following conditions: (1) Teacher Liu is the leader of the reserved subject of the college and must be sent out this time. (2) If you choose Teacher Liu Then, Mr. Zhou must also choose, but not Mr. Zhang. (3) Only Mr. Niu can't choose, at least one of Mr. Wang and Mr. Ma can choose. (4) If Mr. Wang is not selected, then also Don't choose Teacher Zhou. If the above statement is true, which of the following must be true? ['Teacher Niu was not selected, Teacher Zhou was selected.', 'Mrs. Liu was selected, Mr. Ma was not selected.', 'Teacher Wang and Teacher Ma are both selected.', 'Teacher Wang and Teacher Niu were not selected.']