Which practice is NOT one of the Five Pillars of Islam?

The Five Pillars of Islam are fundamental acts of worship and the framework for a Muslim's faith and practice. They include Zakat (charity), Salah (prayer), Shahada (faith), and Sawm (fasting during Ramadan). Each of these practices is essential to a Muslim's religious obligations.

Ritual sacrifice, while significant in Islam, particularly during the festival of Eid al-Adha, does not fall under the Five Pillars. This practice is related to the broader obligations and traditions within the faith but is not one of the foundational acts that define a Muslim's relationship with God. The correct answer reflects the understanding that the Five Pillars are specifically outlined acts of worship that serve as the core principles of a Muslim's beliefs and actions.