In making the saffron spice, which one of the following parts of the plant is used ?

Saffron is the dried red threads that come from the flower of Crocus sativus — specifically the female reproductive part called the stigma. Each flower bears three long red stigmas that are carefully separated by hand and then dried to produce the spice; this labor-intensive harvesting is why saffron is so costly. Scientific and review sources explicitly identify the dried stigma as the edible spice “saffron,” noting that each flower yields three stigmas (often called threads) which after drying are used for flavoring, coloring, and aroma in food and as a dye [1]. Thus the correct plant part used to make the saffron spice is the stigma.

Sources

1. [1] https://lcm.amegroups.org/article/view/8290/html