In a pedigree chart, the symbols are used to represent individuals and their traits. The correct interpretation among your options is:
b: A shaded circle represents a female with the trait.
To clarify further:
- A shaded circle represents a female with the trait.
- A shaded square represents a male with the trait.
- An unshaded circle represents a female without the trait.
- An unshaded square represents a male without the trait.