Which analogy shows a part-whole relationship?

A fin is to a fish as singing is to a bird.
A leaf is to a tree as a petal is to a flower.
City is to state as state is to town.
A second is to a minute as a minute is to a month.

A leaf is to a tree as a petal is to a flower.

The analogy that shows a part-whole relationship is:

A leaf is to a tree as a petal is to a flower.

The analogy that shows a part-whole relationship is:

A leaf is to a tree as a petal is to a flower.

To understand why this analogy represents a part-whole relationship, we need to focus on the relationship between the two terms in each analogy. In this case, the relationship between a leaf and a tree is that a leaf is a part of a tree - it is one of the components that makes up a whole tree. Likewise, a petal is a part of a flower; it is one of the components that makes up a whole flower.

Analogies are typically used to highlight relationships between two sets of words. In this specific analogy, the relationship being expressed is a part-whole relationship, where the first term (leaf) is a part of the second term (tree), and the second term (petal) is a part of the fourth term (flower).