Select the most appropriate ANTONYM of the underlined word.
Maria thinks the animals that live in freedom have a sad look in their eyes.

The correct answer is Captivity.

To find the correct antonym, we need to understand the meaning of the underlined word, freedom, in the context of the sentence: "Maria thinks the animals that live in freedom have a sad look in their eyes."
Here, "freedom" refers to the state of being free, wild, or not restricted or confined.

Let's analyze the given options to find the word that has the opposite meaning (antonym):
1. Carefree: Free from anxiety or responsibility. This is not the opposite of freedom.
2. Liberty: The state of being free within society from oppressive restrictions imposed by authority on one's way of life, behavior, or political views. This is a synonym of freedom, not an antonym.
3. Surrendered: Having given up or been yielded to the power or control of another. While it relates to a loss of control, it is not the direct opposite of a state of physical freedom or wildness for animals.
4. Captivity: The condition of being imprisoned or confined. This is the direct opposite of living in freedom (especially concerning animals living in the wild vs. in cages or zoos).

Therefore, Captivity is the most appropriate antonym of freedom.