I received an Apple review comment says that they found an issue in my App when they run it on a iPad with iOS version 11.3.1.
I tried my App on an iPad simulator with iOS 11.3 and 11.4 (beta) but the issue was not reproduced.
What I want to do now is to test my App on a simulator with the exact version of iOS mentioned in Apple's review comment - that is 11.3.1
However, I found that iOS 11.3.1 is not available to me through xcode's components dialog - please refer to the screen capture image below for details.
So my question is: how can I create an iPad simulator with iOS 11.3.1 ?
The xcode version that I am using right now is 9.4 beta downloaded from Apple developer center. I also tried xcode version 9.3.1 downloaded from Apple app store. Neither of it gives me iOS 11.3.1 - This line is added through edit after I read Roshan's answer. Thanks to Roshan.