What ritual is central to the Jewish celebration of Rosh Hashanah?

The blowing of the shofar, a ram's horn, is indeed central to the Jewish celebration of Rosh Hashanah. This ritual marks the beginning of the Jewish New Year and serves multiple purposes within the context of the holiday. Firstly, the shofar's sound is a call to repentance, urging individuals to reflect on their actions over the past year and to make amends in preparation for the upcoming year. The shofar's sounds, which include a series of blasts, are considered deeply meaningful and are a significant element of the religious observance.

The other options, while they may be relevant in other Jewish contexts, do not hold the same central place in Rosh Hashanah. Lighting candles is associated with various Jewish holidays, but it does not specifically define this celebration. Reading the Torah is a common practice in many Jewish rituals, but it is not the primary focus of Rosh Hashanah. Reciting the Haggadah is specifically tied to Passover and the Seder meal, making it unrelated to the themes and practices of Rosh Hashanah. Thus, the blowing of the shofar stands out as the defining ritual of this solemn and reflective holiday.