Correct Answer: Investigation
 

Solution : The correct answer is  option 2- Investigation.
Key Points:
In the preceding phrase, it is stated that the Central Bureau of Investigation conducted the entire enquiry of the crime.
- Let's examine the definitions of the following words:
A scheduled public or social occasion is called an event.
- Example: The event was held successfully.
An investigation is a formal review of the information around a circumstance or a crime.
- Example:The investigation was done without any bias.
Scene refers to the location where an event takes place.
- Example: People were present in at the scene when he was honored 
A succession of planned or overseen events is referred to as proceeding.
- Example: The proceedings of the investigation were discussed among the officers.
Consequently, in light of the definitions of the terms used.
- Investigation (option 2) is a good fit for the provided blank.