Option Explicit On is a recommended good practice with Visual Basic .Net. It helps you as the developer to produce cleaner, more stable, more bug-free, more maintainable code. In some cases it may also help you write programs with better performance too!
with ref to https://support.microsoft.com/en-in/kb/311329#bookmark-3 option strict is also can be used instead of option explicit. Option strict inherits option explicit.