Matters that are confidential must not be made …

Step 1: Analyze the question The sentence is: "Matters that are confidential must not be made ........." We need a word that fits both meaning and grammar.

Step 2: Understand the concept "Confidential" means secret or private, something that should not be shared widely. So the missing word should be the opposite idea: something that stops confidential matters from being revealed to everyone.

Step 3: Test each option

• A. public: "must not be made public" is a very common phrase meaning not revealed to people in general. It fits perfectly.
• B. popular: "made popular" means made widely liked. It is about being liked, not about being known, so it doesn't fit.
• C. unreasonable: "made unreasonable" has no logical link to secrecy.
• D. uncertain: "made uncertain" means made doubtful, which has nothing to do with confidentiality.

Step 4: Answer The correct answer is A. public. Confidential matters are private, so they must not be "made public" (disclosed to everyone).

Tip: Look for the antonym relationship. When a sentence describes something as confidential, secret, or private, the blank is often filled by its opposite idea, public. Also learn common collocations like "make public," "make known," and "keep secret," because WASSCE and JAMB often test these.