The 4th paragraph was about situations in which regulation is needed but can't be provided because the internet is so vast and unwieldy!
A: this isn't calling into *question* the argument in the 2nd para.
B: this isn't *questioning* the 1st para.
C: No, the 4th para has nothing to do with trademarks.
D: the 3rd para was only about trademarks. This is not correct.
E: Yes; the general claim in the 1st para is how the internet presents difficulties for traditional legislation and law enforcement.