Answer: C

This question examines the educational quotes of different educators.

“Be a teacher all your life, and learn to be a teacher all your life” is the famous saying of the educator Mr. Yu Yi. Yu Yi graduated from the Education Department of Fudan University in 1951 and was named one of the first batch of special teachers in the country in 1978. She dedicated her all to the cause of people's education and won the highest honor given to teachers by the party and the people. However, she always said that she had "been a teacher all her life and been learning to be a teacher all her life."

Item C was elected.

Item A: Tao Xingzhi, Chinese people's educator, thinker, great democratic fighter, patriot, one of the main leaders of the Chinese People's Salvation Association and the China Democratic League. He successively founded Xiaozhuang School, Life Education Club, Shanhai Engineering Group, Yucai School and Social University. He put forward three major propositions: "Life is education," "Society is school," and "Teaching and doing are integrated." Life education theory is the theoretical core of Tao Xingzhi's educational thoughts. If it does not match the question, it will be excluded.

Item B: Ye Shengtao, a modern writer, educator, literary publisher and social activist, is known as an "excellent language artist". Ye Shengtao's educational thought made an original, systematic and important contribution to the modern education theory with Chinese characteristics. This educational thought, taking the practice of China's education reform as its logical starting point, formed the materialist dialectical theory of China's education reform; he proposed that "teaching is for the sake of not teaching." If it does not match the question, it will be excluded.

Item D: Comenius, the father of education, authored "The Great Theory of Teaching". Comenius conducted a detailed analysis and explanation of the teaching content, methods and art, and proposed A set of teaching principles, such as the principle of intuition, the principle of gradualness, the principle of consolidation, etc., lay the theoretical foundation of teaching theory. He believes that "teaching is the most glorious profession under the sun." If it does not match the question, it will be excluded.

So the correct answer is C.