Which type of memorial consists of a top piece supported by two standards, commonly used in cemeteries?

The correct choice is the type of memorial that typically features a top piece supported by two vertical standards, commonly found in cemeteries, which is a bench. Benches in cemeteries are designed to provide a place for reflection and remembrance, often featuring a flat surface where inscriptions or memorials can be placed. The two standards support this flat top, creating a stable and inviting space where visitors can pause to remember their loved ones.

Other types of memorials, while they may limit or enhance the environment of a cemetery, do not share this same structure. For example, a tombstone, which is a vertical grave marker typically showing the deceased's details, lacks the horizontal design supported by standards that characterizes a bench. Kiosks are generally freestanding structures used for information or display and do not serve as memorials in the cemetery context. An obelisk, although a monumental structure, is generally a tall, tapering four-sided pillar that stands alone rather than having a flat top supported by two standards. Thus, the specific structural characteristics of a bench make it the correct answer for this question.