Which best explains how roots and affixes can be used to det

Which best explains how roots and affixes can be used to determine the meaning of the following academic word: unilateral?    1.The prefix uni- means “one” and the root lat means “side”; so unilateral means one-sided. 2. The prefix uni- means “alone” and the root lat means “carry”; so unilateral means carried alone. 3. The prefix uni- means “alone” and the root lat means “carry”; so unilateral means an individual burden. 4. The prefix uni- means “one” and the root lat means “side,” so unilateral means flat.