How would you define something that is 'tiny'?

The term 'tiny' is defined as something that is extremely small in size, so the choice indicating this definition is correct. When we consider the nuances of size, we can see that 'tiny' implies a scale that is significantly less than what is typically expected or understood as normal or average.

For instance, a tiny object could be something like a grain of sand or an ant, which are both much smaller than common everyday items. This contrasts sharply with the other descriptions provided, which suggest sizes that are average, large, or moderately sized—none of which align with the clear and specific connotation of 'tiny.' Thus, the correct choice effectively captures the essence of the term as it relates to size.