Final answer:
The word 'Distributed' would change the meaning of the sentence as it implies a different structural organization, suggesting that the DNA is spread throughout the cell rather than localized in the nucleoid.
Step-by-step explanation:
In the context of prokaryotic cells, the DNA is located in a region called the nucleoid and is not enclosed by a membrane. The original sentence states that the DNA is not contained inside a membrane. Among the options provided, the word that would CHANGE the meaning of the sentence if it replaced contained would be Distributed, as it implies the DNA is spread out evenly or in different areas within the cell, rather than being localized in a specific region like the nucleoid.
Words such as Enveloped, Secured, and Concealed imply containment and do not significantly alter the original meaning of the sentence. Concealed infers hiding or not allowing to be seen which is similar to how the nucleoid is not compartmentalized by a membrane thus not visible as a distinct entity. However, Distributed, on the other hand, suggests a different structural organization of the DNA, fundamentally changing the understanding that, in prokaryotic cells, the DNA is concentrated within a specific non-membrane bound area of the cell.