Question 80·Medium·Transitions
Scientists once believed that the deep sea was largely devoid of life because sunlight could not penetrate its dark waters. _____ recent explorations using remotely operated vehicles have revealed vibrant ecosystems thriving around hydrothermal vents.
Which choice completes the text with the most logical transition?
For transition questions, first summarize each sentence or clause in simple words and decide how the ideas relate: do they show contrast, cause-and-effect, example, addition, or similarity? Then quickly label what each answer choice usually signals and eliminate any that don’t match that relationship. Always plug your best remaining option back into the sentence to check that the tone and logic flow smoothly.
Hints
Identify the two main ideas
Restate the first and second sentences in your own words. Does the second sentence agree with the first, or does it challenge it?
Think about the relationship between old belief and new evidence
Is the new information a result of the old belief, an example of it, something similar to it, or something that goes against it?
Match transition types to relationships
Ask what each choice usually does: one shows result, one shows contrast, one shows example, and one shows similarity. Which type fits the relationship you noticed between the two sentences?
Step-by-step Explanation
Understand what each sentence is saying
Read the first sentence: scientists once believed the deep sea was mostly lifeless because no sunlight could reach it. This is an old idea.
Now read the second sentence: recent explorations have found vibrant ecosystems in the deep sea. This is a new finding that challenges the old belief.
Decide how the two ideas relate
Ask: Does the second sentence support, explain, give an example of, or contradict the first sentence?
The first says “largely devoid of life”; the second says “vibrant ecosystems thriving.” These ideas clearly oppose each other. The relationship is that the new evidence goes against the old belief.
Match the relationship to the type of transition
Now think about what each type of transition usually signals:
- One option signals a result or conclusion from what came before.
- One introduces a contrast or exception.
- One introduces an example of the previous statement.
- One signals a similarity or continuation of the same idea.
Since the second sentence contradicts the first, you need the option that introduces a contrast between the old belief and the new discovery.
Choose the transition that shows contrast
The transition that clearly introduces a contrast between the earlier belief and the new, opposing evidence is "However,", so that is the best choice.