Moreover, a lecturer is a professional i.e. he/she possesses skills and is trained on how to deliver content to students in the most effective manner. This could be done by demonstrations, real applications, enabling students to understand better and giving them a more relevant approach to content rather than them acquiring knowledge from other sources such as internet, text books, magazines, newspaper etc.
I also agree with the assumption that the questions in exams should come only from what has been covered in class. One of the reasons to my agreement is that the purpose of examinations is to be evaluated on the content that has been taught a student. It is a true reflection of how well a student grasped the content he/she was taught. Therefore, the lectures would get a feedback on how well the students have understood the content. If majority of the students pass, the lecturer would continue using the same methods to give out knowledge to the students, making the learning process easier.
Furthermore, it is never certain that the information provided by other sources outside the classroom is correct. For example, if the questions appear from something not covered in class and a student uses the answer he/she read from ask.com (a website which includes answers from other individuals) could lead to him/her failing the exam as the answer could be incorrect. Also,