Substance a doesn't have fixed melting and boiling points substance b has fixed melting and can't be broken down by chemical reaction substance c has fixed melting and boiling points and breaks down into simpler substances when heated

The answer would be

Electrical charges of ionic bonds

There is no reason to think the results are biased or not conducted properly but you should not assume the results are correct just because they were done in a laboratory so the answer would be c. it is likely to be reliable because the results support the conclusion presented.

Green is technically every other color but green but the other wavelengths of the other colors get absorbed by the object and the wavelength of the color green gets reflected