Correct answer: A. Service to poor and sick people
Explanation: The direct answer is A: Service to poor and sick people. Mother Teresa became internationally known for caring for people who were poor, ill, homeless, or neglected. The underlying idea is humanitarianism: helping human beings because they need support, dignity, and compassion, not because they can give something in return. Her religious organization, the Missionaries of Charity, worked among vulnerable people, especially in India. Therefore the reasoning is: the question asks about the broad value connected with her work; her well-known activity was compassionate service; so option A is the best match. Option A is correct because serving the poor and sick describes her public work. Option B, imperial conquest, means gaining territories through an empire and has no connection with her charitable mission. Option C, military monarchy, describes a political system ruled by a monarch with military power, not humanitarian service. Option D, piracy, means robbery at sea and is completely unrelated. Memory cue: Mother Teresa means compassion, charity, and service to the needy.