What do you think about this rumour?

Tiffany was suppose to rap the part "Ayo GG! " in 'I Got A Boy' MV. But SooYoung and HyoYeon wanted that part too because it was the most important part and it will bring out the atmosphere of 'I Got A Boy'. The manager was thinking about this over and over again. And in the end, they decided to give it to SooYoung. Tiffany wasn't really happy about it. Originally suppose to be hers. Hyoyoen was upset too. So, it was heard that the three of them didn't really talk much during the period of time. But during live or they have a gathering, they were told to be more happier and try to talk to each other and smile more. So no choice,the three of them had to pretend.

Conversation heard between them by an unknown person who leak out this incident -truth-
Sooyoung: 'Tiffany, I know you're not happy but just let me try this part this time okay?'
Tiffany: 'But it suppose to be mine..'
Sooyoung: 'I know that Fany.*frustrated voice* . But now it'smine. Anyway, you still have lots of part right? I've only had a little.'
Hyoyeon: 'Well , stop it both of you! *angry voice* just cut it out! I don't care
The other members look at them and comfort them. Asking them to cool down.
The three of them remain cold-shoulder for a period of time..