A constitution that requires a plebiscite or a referendum to be amended is

Step 1: Analyze the question The question asks what type of constitution needs a plebiscite or referendum (a direct vote by the people) before it can be amended.

Step 2: Explain the concept Constitutions are classified by how easily they can be changed:

• Flexible constitution: Can be amended through the ordinary legislative process, with a simple majority in the legislature. Example: the United Kingdom.
• Rigid constitution: Requires a special, difficult procedure to amend. This may be a two-thirds or three-fourths majority in the legislature, approval by state legislatures, or a referendum or plebiscite. Examples: the USA and Nigeria (1999 Constitution).
• Written vs. unwritten: This is about whether the constitution is codified in a single document. It does not describe how hard the constitution is to amend.

Step 3: Apply to the question Requiring a plebiscite or referendum means a special, difficult process beyond ordinary lawmaking. Amendment is not easy, so the constitution is rigid.

• A. Written: describes the form, not the amendment procedure.
• B. Flexible: the opposite, because flexible constitutions are easily amended.
• C. Rigid: correct.
• D. Unwritten: does not relate to the amendment procedure.

Step 4: Answer The correct option is C. rigid.

Exam tip: Link the words: Rigid = Raised hurdles (special majorities, referendum). Flexible = Fast and easy (ordinary law-making). When you see "referendum," "plebiscite," or "two-thirds majority" tied to amendment, think rigid.