In the great gatsby does wealth alone decide which class a character belong

Yes the wealth does do that

I believe so because Gatsby was a wealthy man who was poor at first and worked his way to become rich (aka at the top) and the woman he loved was also rich and had a high class. The poorer people were lower class in the book/movie as well

the correct answer is:

this is an example of the writer telling through description rather than showing through dialogue.

sometimes writers like to explain explicitely what's happening instead of adding dialogues of the situations., which is the case in this passage,

if this isnt a true or false than they have equal amount of importants