もっともな (translations)→ believable fair just practical sound understandable
当然 (translations)→ automatically deserve eventually expectantly fully inevitably naturally obviously only perfectly proper readily reasonable should understandably well
当然ながら (translations)→ clearly so usual
当然の (translations)→ belong inevitable natural undisputed
納得できる (translations)→ accept know obvious
普通 (translations)→ straightforward typically usually