Answer:
Red
Step-by-step explanation:
The Germans were bombing British naval ports and airfields but then Churchill ordered a small bombing of a Berlin which didn't do much damage but infuriated Hitler who ordered all of his pilots to focus civilian targets in London. This gave the RAF [royal air force] time to rebuild and repair all there planes and control centers that had been damaged. This meant that shortly after the RAF were back in action they were defending the civilian areas that were being hit the most. They also had upgraded there radars so they could tell when an attack was coming and if it would be a large one or a small one. As the Germans continued to bomb civilians they were using up more of their resources and losing more planes as the British got better at repelling there attacks and shooting down their planes. Eventually the Germans had to give up and air superiority was placed firmly in british hands.