First I'll list the transition words/phrases found in the paragraph:
After
Also
In addition
Next
however,
Yet
The transition words/phrases that indicate time relationship would be 'after', and 'next'.
It is most likely to be D. Sometimes but not always the first sentence is what the passage is mostly about.
To present all sides of the story
That's a weird question. It could be any if the above, and without more context it's impossible to know. The most general one that applies to pretty much all claims is "it takes a clear position", so I would go with that.
The answer for this question is A.?
