With sand casting, probably the most common method, ordinary sand is used as the mold material. A two-piece mold is formed by packing sand around a pattern that has the shape of the intended casting.

• A. Investment casting uses wax patterns
• B. Sand casting uses ordinary sand
• C. Die casting uses metal mold under pressure
• D. Lost foam uses foam pattern

Answer: (B)

The main idea here is that sand casting uses ordinary foundry sand as the mold material. In this method, a pattern that matches the desired outside shape is placed in a flask and sand is packed around it to form a two-piece mold (often called the cope and drag). Once the sand is packed, the pattern is removed, leaving a cavity that mirrors the casting. Molten metal is then poured into that cavity and, after it solidifies, the mold is broken away to reveal the part. This approach—sand, pattern, two-piece mold formed by packing around the pattern—is why this option is the correct description.

Sand casting is popular because it’s inexpensive and adaptable for large or complex shapes and a wide range of metals. Other options describe different casting methods (investment casting uses wax patterns invested in ceramic shells; die casting uses metal molds under high pressure for high-volume parts; lost-foam uses a foam pattern that’s replaced by metal), which explains why they don’t fit the description of sand casting.