The fibrous septa that support the breast are known as Cooper's ligaments. These ligaments are fibrous tissue structures that extend from the skin to the underlying fascia of the breast, providing support and helping maintain the shape of the breast.
- Cardinal ligament supports the uterus, not the breast.
- Mackendrodt's ligament is related to the pelvic region and does not support the breast.
- Broad ligament is also associated with the uterus and pelvic region, not the breast.
Thus, the correct answer is (2) Cooper's ligament.