All perfect praise be to Allah, The Lord of the Worlds. I testify that none is worthy of worship except Allah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.
There is no harm – Allah willing – for a son to express his opinion that is contrary to that of his parents’ in a matter where the views differ, if that is done within the limits of Islamic etiquette, by speaking to them with softness, gentleness and humbleness.
It is more appropriate to give an introduction before that with good words, such as praising their opinion, and asking them to allow him to give his view, and asking their forgiveness if his opinion opposes theirs, while avoiding anything that would lead to their anger, even if it is very insignificant.
Allah Says (what means): {And your Lord has decreed that you not worship except Him, and to parents, good treatment. Whether one or both of them reach old age [while] with you, say not to them [so much as], "uff," and do not repel them but speak to them a noble word.} [Quran 17:23]
Additionally, ‘Aa’ishah narrated that the Prophet said: “Whenever gentleness is found in something it beautifies it, and whenever it is withdrawn from something it leaves it defective." [Muslim]
For more benefit on the limits of obedience to parents, please refer to Fataawa 271255, 131695, and 123554.
Allah knows best.