Statement I: Students were caught cheating using hidden devices. Statement II: Surveillance cameras were installed in the exam halls.

Explanation

Option A is correct because it establishes that the act of students cheating (Statement I) is the reason for the installation of surveillance cameras (Statement II). The need for surveillance arises as a response to the cheating incidents. Option B is incorrect as it suggests a reversal of cause and effect, implying that surveillance cameras caused cheating, which does not logically make sense. Option C incorrectly indicates that the statements are unrelated, overlooking the clear relationship where cheating leads to the implementation of surveillance. Lastly, Option D is incorrect as it suggests a common cause for both events, which is not supported by the information given; instead, the statements demonstrate a clear cause-and-effect relationship.