Five jumbled sentences (labelled 1, 2, 3, 4, and 5), related to a topic, are given below. Four of them can be put together to form a coherent paragraph. Identify the odd sentence out and key in the number of that sentence as your answer

Correct Answer: "The research team used deep-sea chambers that land on the seafloor and enclose the seawater, sediment, polymetallic nodules, and "

Step-by-step Explanation:

To identify the odd sentence out, we need to analyze the thematic relationship between the sentences and find the four that combine to form a coherent, logical paragraph.
Let us examine the flow and connections between the sentences:

1. Sentence 1 introduces the general context of ocean oxygen production: "About half of all the oxygen we breathe is made near the surface of the ocean by phytoplankton that photosynthesize just like land-dwelling plants." This serves as an excellent introductory sentence, establishing the baseline knowledge about how oxygen is typically produced in oceans (near the surface, via photosynthesis).
2. Sentence 5 shifts the focus to the deep ocean: "The deep-sea rocks, called polymetallic nodules, don’t only host a surprising number of sea critters." This sentence introduces the subject of "polymetallic nodules" (deep-sea rocks) and sets up a transition to another function they perform.
3. Sentence 2 connects directly to the nodules introduced in Sentence 5: "A team of scientists that includes Boston University experts has discovered they also produce oxygen on the seafloor." Here, the pronoun "they" refers back to the "polymetallic nodules" from Sentence 5.
4. Sentence 4 concludes the narrative by reflecting on the discovery: "The discovery is a surprise considering oxygen is typically created by plants and organisms with help from the sun—not by rocks on the ocean floor." This connects back to Sentence 1 (which mentioned oxygen being created with the help of the sun/photosynthesis) and highlights the contrast with the new discovery.

Together, the sequence 1 → 5 → 2 → 4 forms a complete, coherent paragraph detailing the surprising discovery of oxygen production by deep-sea rocks compared to typical surface photosynthesis.

Why the remaining sentence is the odd one out:
The sentence "The research team used deep-sea chambers that land on the seafloor and enclose the seawater, sediment, polymetallic nodules, and " describes the specific experimental methodology and tools used to conduct the study. Furthermore, it is grammatically incomplete. It does not fit into the high-level narrative structure of the discovery established by the other four sentences, making it the odd sentence out.