Final answer:
The drink made of water, barley, and pennyroyal that was consumed in rites for Demeter and Persephone during the 19th Boedromion is called kykeon. The correct option is c. Kykeon.
Step-by-step explanation:
The drink made of water, barley, and pennyroyal, mentioned in the Homeric Hymns and consumed during the 19 Boedromion after a day of fasting in honor of Demeter and Persephone, is known as kykeon.
This beverage is not to be confused with nectar or ambrosia, which were foods of the Greek gods, or with moly, a mythical herb. Kykeon played a significant role in the religious rituals, specifically within the Eleusinian Mysteries, which celebrated the myth of Demeter's search for her abducted daughter Persephone.
The consumption of kykeon was a part of this ancient festival, often correlated with Demeter's fast during her search, and was ritualistically linked to the restoration of normality after a period of 'abnormal' behavior during festivities. The correct option is c. Kykeon.