In the Brassicaceae family, what is a common characteristic of their flowers?

Flowers in the Brassicaceae family, commonly known as the mustard or cabbage family, are characterized by their structure, which typically features four petals arranged in a cruciform (cross-shaped) pattern. This characteristic is a defining trait of the family and is one of the reasons plants in this group are easily identifiable. The flowers are usually small and can vary in color but are often white, yellow, or purple.

The other options highlight characteristics that are not typical of Brassicaceae flowers. For instance, large clusters of colorful petals and bold fragrances generally describe flowers in different plant families, particularly those that rely on attracting specific pollinators. Cylindrical flower heads are more characteristic of other families such as Asteraceae (the daisy family). Thus, the four-part flower structure is what distinctly represents the Brassicaceae family and is crucial for their classification.