Which is the most important ceremony in scrum?

Scrum’s roles, events, artifacts, and rules are immutable and although implementing only parts of Scrum is possible, the result is not Scrum. Scrum exists only in its entirety and functions well as a container for other techniques, methodologies, and practices.

The Scrum Guide

Thanks @Simon for the reply.

I believe Sprint Review is the most important ceremony as we receive client feedback in that which becomes the 'driving' factor for the next sprint. 

What are your thoughts on this?

When I search this question on google, I can see Daily Stand-up, Retrospective are also mentioned as most important.

So got confused, if we need to come up with any one, which one is that? and Why?

@SUMIT AGRAWAL, Each event has its purpose so wouldn't it be right to consider that all the events are equally important? If one event was more important than the other would it not cause a bias, perhaps people will start attending the "unimportant" meetings?

Each Scrum Event was defined for a specific purpose and everyone of those purposes are as important as all the others. This question is somewhat like asking which part of an automobile is most important.  In reality without all of the parts none would be important. 

It would be quite juvenile to ask such a question. All meetings have a clear agenda and all are important in their own context.

I hope, you are not getting confused after reading questions on a third party website on agile ceremonies. 

Below is excerpt from Open Scrum Assessment.

Scrum is meant to be implemented as prescribed in the Scrum Guide.  The five events in the Scrum Guide are mandatory, each event has a specific purpose.