______ scientists analyzed the data from the deep-sea probe, they discovered evidence of previously unknown microbial life forms.
Which choice completes the text so that it conforms to the conventions of Standard English?
- A
And
- B
However
- C
Therefore
- Dcheck_circle
When
Explanation
"When" creates a dependent clause that precedes the main clause with a comma. The others are coordinating conjunctions or adverbs requiring different structures.