Instructions: 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".
Input: [header] How to find a stud [title] Invest in a tool that allows you to identify studs in your walls. [step] These are often called stud finders or stud sensors. They can be purchased at hardware shops, home improvement retailers or department stores. <sep> (A) If your walls are too big, it is best to purchase a stud removal tool or flush viewer. Other tools you may want to purchase are, , or. (B) You should invest in a tool that allows you to identify studs in various sizes, shapes, lengths and textures in wooden and metal objects. Do not over charge, though, especially when searching for stud space. (C) [title] Determine what kind of stud finder you have. [step] Some stud finders are magnetic, so you will feel a pull when a stud is identified based on the presence of nails or wires running along the stud. (D) [substeps] Any tool you buy that allows you to recognize studs is a stud sensor. These m6an stud sensors can be found in most hardware stores.
Output:
C