For decades, paleontologists operated under the assumption that all non-avian dinosaurs were strictly land-dwelling creatures, lacking the adaptations required for swimming. However, while studying the fossilized remains of the Cretaceous-era theropod *Spinosaurus* in Morocco, researcher Nizar Ibrahim realized that the dinosaur's dense, compact bones and unique paddle-like tail indicated an aquatic ______ conclusion that challenged the long-held scientific consensus regarding dinosaur habitats.
Which choice completes the passage so that it conforms to the conventions of Standard English?
- Alifestyle; a
- lifestyle: aAnswer
- Clifestyle, it was a
- Dlifestyle; it being a
Answer
lifestyle: a
The correct answer is 'lifestyle: a'. A colon is grammatically appropriate here because the clause preceding the colon is independent, and the phrase following it is an appositive noun phrase ('a conclusion...') that explains the significance of the preceding clause.
Step-by-Step Solution
Key Concept
Using colons to connect independent clauses to explanatory noun phrases, and avoiding semicolons or commas where they create fragments or comma splices.