The correct answer is 4. The nature of heaven
Step-by-step explanation:
Summa Theologica is the most famous work written by Thomas Aquinas who was an Italian Catholic priest and theologian in the thirteen century. This book published in 1485 was created by Aquinas a guide for theology students including the main teachings of the church, information about the sacraments, man's purpose, the creation, man's virtues, the angels, the life of Christ and God and a small section about the purgatory. In this way, the Summa Theologica deals with different topics related to the Catholic religion including sections that deal with man, Christ, God and angels, and even the purgatory, but it does not include any section about the nature of heaven, thus the one the Summa Theologica does not discuss is 4. The nature of heaven.