The correct answer is (a) J. Habermas.
J. Habermas is a German sociologist and philosopher who is considered one of the most important thinkers of the 20th century. He is best known for his work on social theory, philosophy of language, and critical theory.
In his book The Theory of Communicative Action, Habermas argues that modernity is an unfinished project. He argues that the Enlightenment project of creating a rational and just society has not been fully realized. He believes that we need to continue to work towards this goal through critical thinking and dialogue.
George Ritzer is an American sociologist who is known for his work on globalization, consumerism, and McDonaldization. He is the author of several books, including The McDonaldization of Society and The Globalization of Nothing.
Anthony Giddens is a British sociologist who is known for his work on structuration theory and globalization. He is the author of several books, including The Constitution of Society and Runaway World.
Wernir Sombart was a German economist and sociologist who is known for his work on capitalism and socialism. He is the author of several books, including The Quintessence of Capitalism and Socialism.
In conclusion, the correct answer is (a) J. Habermas.