To answer this question, you need to know the name chosen by Cardinal Joseph Sarto when he became pope. Let's go through each option to understand why it is correct or incorrect:
Option A) John XXIII - This option is incorrect because John XXIII was the papal name chosen by Angelo Giuseppe Roncalli, not Cardinal Joseph Sarto.
Option B) Paul VI - This option is incorrect because Paul VI was the papal name chosen by Giovanni Battista Montini, not Cardinal Joseph Sarto.
Option C) Benedict XVI - This option is incorrect because Benedict XVI was the papal name chosen by Joseph Ratzinger, not Cardinal Joseph Sarto.
Option D) Pius X - This option is correct because Pius X was the papal name chosen by Cardinal Joseph Sarto when he became pope.
The correct answer is D. Pius X. This option is correct because Pius X is the name that Cardinal Joseph Sarto took when he became pope.