Injection moulding is best described as which statement?

• A. Process for making hollow plastic forms by blowing air into heated thermoplastic.
• B. Direct introduction of molten plastic under pressure into a die, which then cools rapidly, allowing the formed object to be released from the mould.
• C. Creates uncomplicated hollow shapes by sucking a heated plastic over a mould.
• D. Process for creating large hollow plastic objects.

Answer: (B)

Injection moulding works by forcing molten plastic under pressure into a mould cavity (a die), where it cools rapidly and solidifies, and then the finished part is ejected from the mould. This description matches injection moulding exactly because it emphasizes the direct injection of molten plastic into a mold and the quick cooling that lets the part be released in one piece with good detail and precision. The other options describe different manufacturing processes: blowing air into heated plastic is blow moulding, which creates hollow forms by inflation; drawing a heated sheet over a mould with suction is thermoforming or vacuum forming; and claiming it creates large hollow objects is too vague and not specific to injection moulding.