Correct answer: A. Freedom of expression
Explanation: The governing concept is freedom of expression, an important part of liberty and democratic participation. It allows people to communicate opinions, questions, criticism, and creative ideas through lawful means, subject to reasonable limits that protect safety, reputation, and the rights of others. Option A is correct because it directly names the right connected with expressing ideas. Forced labour in B is exploitation, illegal detention in C is an unlawful deprivation of liberty, and insulting behaviour in D is harmful conduct rather than a right. These options describe violations or abuses, not protected expression.