Because gold is better than yellow
It is the quality of the diamond that makes it sparkle not so much whether the setting is white or yellow gold
Your gold choice color is a matter of preference. White gold is enjoying greater popularity right now and may sometimes be more expensive, but this is really more a matter of demand and what sellers know they can get. As far as why white gold is white and yellow gold yellow, it's all a matter of the kinds of metal alloys that are combined with pure gold, which is naturally yellow but may be altered. Also, pure gold is too soft not to combine it with other metals for strength.
I don't know what you mean by, "better", but 10K has less gold in it than 14K does. By the way, 24K gold is more or less pure gold.
Yes yellow is better than orange
Yes yellow is better than brown
Yes yellow is better than white
Rose gold is better and could be expensive because it is rare but its only a mixture of yellow gold and copper. but the color could go bad if any perfumes or cremes are accidentally put on it. Yellow gold (pure gold) is more expensive than an alloyed gold.
Yes yellow is better than red.
Yes green is better than yellow
Yes black is better than yellow
Because orange is better than yellow.
No