This is a question I've wanted to ask Japanese natives for a while but have never gotten the chance. In Japanese there are many more "sentences" that end unfinished(at least if we are comparing to English). Sometimes these just end in particles like を、に etc and are very clear(at least to me) as to what is implied afterwards. Although sometimes I struggle to see exactly what would come after particles like から、ので etc. How do Japanese natives "think", perhaps unconsciously, about exchanges like this?
「これは？」 「どうした，サイエ？」 「いえ、どこからかピンク色の萌え電波受信したので」 「？」
Pardon the example but it was the most recent thing I was reading. In this situation he and サイエ are both on the battlefield and she "picks up" a signal and then this very brief exchange leaves our friend confused. Now, how does one actually look at what this ので is doing?
1) Is it used by her to explain to him why she spoke?
2) Does it have an obvious bit afterwards that is implied (Even if one wasn't on the battlefield I'm sure one would find that picking up a ピンク色の萌え電波 would be interesting/surprising)
3) If it's not one of the above how would a native think about this?