Final answer:
The word "wad" best matches option (a) heap, as it refers to a small mass of soft material typically folded or rolled up, similar to a loosely assembled collection of items. The correct option is a.
Step-by-step explanation:
The word "wad" most closely matches the option (a) heap. The word "wad" refers to a small mass of soft material, often folded or rolled up for easy insertion into a space such as the mouth, a hole, or any other cavity, or it can be used to describe a bundle of paper or banknotes.
None of the other options—a stack of something (b), a warning or reprimand (c), or an odd or peculiar behavior (d)—properly match the meaning of "wad". Therefore, the correct answer is (a) heap.
A heap is a collection of items thrown together irregularly, which can sometimes resemble how a wad appears, especially if you envision a wad of clothing or paper. This is not a perfect synonym, but it is the closest among the provided choices. The correct option is a.