P, Q, R and S are masks made of wood, rubber, plastic and metal, respectively. Which of the following statements is/are TRUE?

Question

Coloured strips are printed on a transparent sheet as shown below. The bottom half of this sheet is folded backwards along the PQ axis to form a semi-circle. Which of the option(s) will be a part of the resultant semi-circle?

Answer 1

Option A: Rubber (Q) stretches enough to be pulled from a single mould despite its shape, so this is correct.
Option B: Plastic (R) is rigid and fully encloses its shape, so it actually needs a mould that opens in parts, not a one-piece mould, so this is incorrect.
Option C: Metal (S) can be shaped using a single-use cast such as sand or lost-wax casting, which counts as a one-piece mould process, so this is correct.
Option D: Wood (P) is hand-carved rather than moulded, so each piece is one of a kind and cannot be mass produced, so this is correct.

A, C, and D are correct.

Answer 2

Option A: Rubber (Q) stretches enough to be pulled from a single mould despite its shape, so this is correct.
Option B: Plastic (R) is rigid and fully encloses its shape, so it actually needs a mould that opens in parts, not a one-piece mould, so this is incorrect.
Option C: Metal (S) can be shaped using a single-use cast such as sand or lost-wax casting, which counts as a one-piece mould process, so this is correct.
Option D: Wood (P) is hand-carved rather than moulded, so each piece is one of a kind and cannot be mass produced, so this is correct.

A, C, and D are correct.

Answer 3

Another way in is to name the real manufacturing route each material would actually use in industry, then check whether the statement describes that route correctly.

Option A: Rubber items like Q are typically compression or injection moulded and then simply flexed out of the mould, a well-known single-mould-piece production route, so this statement is correct.
Option B: Plastic items with a fully closed form like R are made by injection moulding into a mould that splits into two or more parts to release the rigid piece; describing that as needing only one piece misrepresents the route. Incorrect.
Option C: Detailed metal pieces like S are commonly produced by casting routes where the mould material itself is sacrificed after each pour, which is functionally a one-piece-mould route even for intricate shapes. Correct.
Option D: Wood pieces like P go through a carving route, which is a subtractive craft process rather than any kind of moulding route, and craft-by-hand naturally means no two outputs are identical. Correct.

Matching each material to its real manufacturing route confirms rubber and metal can go through a single-mould-piece process, plastic cannot, and wood is not moulded at all.

So the correct answer is A, C, and D.

Answer 4

Another way in is to name the real manufacturing route each material would actually use in industry, then check whether the statement describes that route correctly.

Option A: Rubber items like Q are typically compression or injection moulded and then simply flexed out of the mould, a well-known single-mould-piece production route, so this statement is correct.
Option B: Plastic items with a fully closed form like R are made by injection moulding into a mould that splits into two or more parts to release the rigid piece; describing that as needing only one piece misrepresents the route. Incorrect.
Option C: Detailed metal pieces like S are commonly produced by casting routes where the mould material itself is sacrificed after each pour, which is functionally a one-piece-mould route even for intricate shapes. Correct.
Option D: Wood pieces like P go through a carving route, which is a subtractive craft process rather than any kind of moulding route, and craft-by-hand naturally means no two outputs are identical. Correct.

Matching each material to its real manufacturing route confirms rubber and metal can go through a single-mould-piece process, plastic cannot, and wood is not moulded at all.

So the correct answer is A, C, and D.