How to set RANDOM in a batch file?

So i wrote this batch file.

I need to use some kind of random function to choose between 9 .exe fles.

One of those .exe files is "OPTION1.exe", so i'd like the batch to select from "OPTION2.exe, OPTION3.exe..." etc, which are all located in the same folder as the first one.

I'd like to know if it's possible and how to do it.

Thanks for your time.

@echo off
:loop
TASKKILL /F /IM "Software.exe"
TASKKILL /F /IM "Chrome.exe"
TIMEOUT /T 5
cd C:\Users\admin\Documents\Software
start Software
TIMEOUT /T 15
start OPTION1.exe
TIMEOUT /T 10
start connect.exe
TIMEOUT /T 15
cd C:\Program Files (x86)\Google\Chrome\Application
start Chrome.exe 
TIMEOUT /T 400
TASKKILL /F /IM "Chrome.exe"
TIMEOUT /T 10
cd C:\Users\admin\Documents\Software
start disconnect.exe
TIMEOUT /T 15
cls
GOTO loop