B. The government may order immediate change of security features on all computers used by top officials.
Feedback The hacking of computers of a top official may raises security concerns because the top official may be dealing with such issues which need to be held under strict secrecy.
Choice (a) and (c) may not take place because without computers the storage and recovery of data becomes difficult and time consuming.
Choice (b) may take place, because government may first safe guard the computers of other top officials from being hacked.
Loss of data is not the matter here. The problem is that the data is being accessed by unauthorised persons. Hence (d) is not a possible effect.
Hence, (b) is a possible cause.