The correct answer is: Only conclusion I follows.
The first statement, “Most teachers are boys,” means that more than half of all teachers are boys. The second statement, “Some boys are students,” means that there are some boys who are students.
From these two statements, we can conclude that some students are boys. This is because if more than half of all teachers are boys, and some boys are students, then some students must be boys.
However, we cannot conclude that some teachers are students. This is because the second statement does not say anything about teachers. It only says that some boys are students.
Therefore, the only conclusion that follows from the two statements is that some students are boys.