I was down to B, C, and D for this..
I eliminated (B) because I thought it was degree issues and not supported by the passage.
I eliminated (C) because I thought it was too general... the case in the passage does seem to show how the recourse of a citizens' group to the courts represents one way of protecting public interests, but I thought "effective means" was unsupported by the passage.
I just chose (D) because I eliminated the rest and even though I didn't clearly understand what it was talking about, I just circled it. Could someone help me understand why (C) is correct and (D) is wrong?