Its 21!! sorry i was late! :)
Answer:
Radiation , Conduction and Convection
Explanation:
Those are the ways heat is transferred
Answer: Visible light makes up just a small part of the full electromagnetic spectrum. Electromagnetic waves with shorter wavelengths and higher frequencies include ultraviolet light, X-rays, and gamma rays.
As per Weins displacement law the wavelength of light for which we get the peak of the graph is always inversely proportional to the temperature.
So we can say

So here if temperature becomes more cool then wavelength will increase
here we know that



It means the hottest star out of all three is star 3
and coolest star is star 1
now if we star 2 becomes cooler then it means its temperature will go near to star 1 and hence it will more look like to star 1.
So correct answer is
it will look more like Star 1