The correct answer is D. All follow.
The Railway Authorities should clarify the reason of the accident to the Government. This is because the Government needs to know what happened in order to take appropriate action. The Government should also allocate funds to compensate the destruction caused. This is because the people who were affected by the accident deserve to be compensated for their losses. The protection walls of the bridge should be made strong enough to avoid such accidents. This is because it is important to prevent future accidents from happening.
Option I is a good course of action because it will help the Government to understand what happened and to take appropriate action. Option II is also a good course of action because it will help to compensate the people who were affected by the accident. Option III is also a good course of action because it will help to prevent future accidents from happening.
Therefore, all three courses of action are necessary and should be taken.