Sony's company response to my request of updating or unlocking bootloader
Look what they send me after I send them an email in subject of give an update or at least a unlock bootloader to Sony xperia c:
We value the importance of your concern.
In response to your query we would like to inform you that you cannot root your handset because there is no such policy available for rooting of the handset and Sony does not support rooting the handset. If you will root your device in that case our handset will not be considered under warranty.
Sony just shame on you