The correct answer is: C. Either I or II is implicit.
The statement “Nobody can predict as to how long our country would take to contain the unfortunate and disastrous terrorist activities” does not provide enough information to determine whether or not it is impossible to put an end to terrorist activities. It is possible that the statement is simply acknowledging the difficulty of predicting the future, and that it does not mean that it is impossible to stop terrorist activities.
The statement also does not provide enough information to determine whether or not efforts to control the terrorist activities are on. It is possible that the statement is simply acknowledging the difficulty of the task, and that it does not mean that there are no efforts being made to stop terrorist activities.
Therefore, either assumption I or assumption II could be implicit in the statement.