What does Luke 4:4 say in the NASB?
Don't have my NASB in front of me ... but my Holman (which is very close to NASB) says:
But Jesus answered him, 'It is written: Man must not live on bread alone.'
And in the margin the following note:
Other mss add but on every word of God.
The other mss (manuscripts) the translator is talking about would refer to the Greek mss that underlie the KJV.
That has been my point all along. Modern translations relegate variant readings to the margin. And if you would read the preface to the original 1611 version you would see the translators recommend multiple translations when studying the scriptures ... because when you lock yourself into one version (for study) you can possibly arrive at the wrong sense of a particular passage.
The best possible scenario is to take the time to learn the NT Greek language ... then you can translate it yourself and interact with all the versions in print.