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

The correct answer is the sentence: "The research team used deep-sea chambers that land on the seafloor and enclose the seawater, sediment, polymetallic nodules, and " (Sentence 3/Option 3).

Step-by-Step Explanation:

1. Analyze the theme of the sentences:
The sentences revolve around a scientific discovery regarding oxygen production. Specifically, they focus on the traditional understanding of oxygen production versus a newly discovered phenomenon where oxygen is produced on the seafloor (dark oxygen production).

2. Establish the coherence among the other sentences:
Let us examine how the other three sentences connect to form a logical flow:
• Sentence 1 establishes the baseline knowledge: About half of all the oxygen we breathe is made near the surface of the ocean by phytoplankton through photosynthesis.
• Sentence 2 introduces a counter-discovery: A team of scientists has discovered that oxygen is also produced on the seafloor (where there is no sunlight).
• Sentence 4 comments on why this is unexpected: The discovery is a surprise because oxygen is typically created by plants and organisms with help from the sun, not by rocks on the ocean floor.
Together, these three sentences (along with another unnamed sentence in the original five-sentence pool) form a coherent narrative introducing the concept of ocean-surface oxygen production and contrasting it with seafloor oxygen production.

3. Identify the odd sentence out:
The sentence "The research team used deep-sea chambers that land on the seafloor and enclose the seawater, sediment, polymetallic nodules, and " is incomplete and grammatically cut off at the end. Additionally, it shifts the focus to the specific methodology/apparatus (deep-sea chambers) used by the team, rather than describing the core discovery or the conceptual surprise itself. Thus, it does not fit into the primary narrative and is the odd sentence out.