Which question could be tested in a scientific manner?
What causes some people to be color-blind?
Why should people be nice to other people?
Why is the color purple better than the color red?
What are the best shoes to wear when exercising?
What causes some people to be color-blind?
Why should people be nice to other people?
Why is the color purple better than the color red?
What are the best shoes to wear when exercising?