The thing is, study the company well. Match your reason/answer to the business you are hoping to enter.
Coz when I interview engineers or admin people, and they say they are moving for greener pastures -- ah, I will have more questions to ferret out what lies behind that statement.
It usually means: I will not stay around for long, my eye is on overseas employment. Per my experience, they hang around for a year, or shorter, -- and just need to round off their résumé. In our industry, it takes time to train people, and their mistakes are costly or disastrous -- so, training or probation can be expensive on our part.