The word undisputed in paragraph 4 could be best...

Câu hỏi: Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 44 to 50.
Australia has a well-organized and well-structured education system. The education starts at the age of five or six, but it may differ by a narrow margin between states. It starts with the preschool education which is not compulsory and can be offered within a school or separately. The primary and secondary school encompasses the compulsory education for Australians. There are a large number of primary and high school across the country with most of them being public schools. It is estimated that public schools amount to 60% of scholars as opposed to 40% in private settings. All these education providers must be licensed by the government and must fulfill certain requirements including infrastructure and teaching. Universities, on the other hand, are mainly public institutions.
The Australian education system has established a standard curriculum so all scholars will be given the same quality of education. Although there may be some states at which this curriculum is slightly modified, the changes are not significant. The actual curriculum set out in Australia education system is based on important abilities one must have in his life: Literacy, Numeracy, Information and Communication Technology, Critical and creative thinking, personal and social capability, ethical understanding, and intercultural understanding.
There are hundreds of other schools out there that provide technical and further education (TAFE) and vocational education and training (VET). These schools offer short courses, certificates I through IV, diplomas, and advanced diplomas. They focus on training their students in a particular vocation or just to help their students get out into the workplace.
Australian higher education modernity and reputation relies on a huge number of educational providers including universities and different training organizations. Currently, there are 43 universities across the country. The vast majority of universities are public except two private universities. The world- class teaching offered is surely undisputed. Seven Australian universities are traditionally found at the top 100 best universities in the world which is a sufficient indicator to highlight their quality.
Besides universities, more than 5,000 training organizations are registered and accredited. Actual figures show that the number of enrolled students is around 3.8 million with international students sharing more than half a million. There are also 3 self-accrediting higher education institutions. Furthermore, dozens of smaller schools do not grant any degrees or have an accreditation - these are private schools that focus on theology, business, information technology, natural therapies, hospitality, health, law, and accounting.
The word undisputed in paragraph 4 could be best replaced by______.
A. questionable
B. doubtful
C. undeniable
D. unacknowledged