Step-by-step explanation:
Required;
We are required to identify which solid can be formed from discs alone by using the pilling method.
Step-by-step explanation;
If we take several discs of the same radius and begin pilling them one on top of another, we would end up with a cylinder.
Also, if we take several discs which are of decreasing radii, then pilling them one on top of another (starting with the largest to the smallest radius), we would end up with a cone whose shape would be such that the disc with the largest radius would be at the base while the one with the smallest radius would be at the top.
Note however, that this cone would not have a vertex, because the vertex cannot be a circular disc.
Therefore,
ANSWER:
B; Cylinder
E: Cone (not including the vertex)