Answer: D) One hundred years ago, the slave was freed. One Hundred years later, the Negro remains in bondage to the color of his skin.
Explanation: Parallel structure is repetition of the same pattern of words or phrases within a sentence or passage to show that two or more ideas have the same level of importance. From the given options, the sentence that contains parallel structure is option D, becaus of the repetition of the structure in the phrases "one hundred years ago" and "one hundred years later" both followed by a comma.
