Q: In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D".
[header] How to cast metal [title] Get a 2-piece mold frame. [step] To successfully cast metal, you'll first need to acquire a mold frame (also known as a mold flask) made of wood, iron, or a similarly solid material. Make sure the frame comes in 2 parts and is large enough to hold the object you want to cast. <sep> (A) [title] Drill holes for the bottom of the frame. [step] Make sure to drill through the wood like the mouth of a hammer [title] Cut any thin pieces off the frame. (B) [substeps] Look for mold frames online or from specialty metal supply stores. As long as it is sturdy, the specific material used to make your mold frame does not matter. (C) [substeps] Use 3 full coats of cold metal paste, such as lewis sal, instead of steel paste. Place your mold frame on a flat, dry surface. (D) This frame will prevent the object from falling apart when you cast iron objects, and it will give the object some extra room to expand at an angle. [substeps] You could purchase pre-assembled or premixed casts from most home improvement stores.
A:
B