Intangible Assets

Which of the following should be classified as development costs? 1) Braynee Co has spent $300,000 investigating whether a particular substance, flubber, found in the Amazon rainforest is resistant to heat. 2) Cleverclogs Co has incurred $120,000 expenses in the course of making a new waterproof and windproof material with the idea that it will be used for ski-wear 3) Ayplus Co has found that a chemical compound, known as XYX, is not harmful to the human body. 4) Braynee Co has incurred a further $450,000 using flubber in creating prototypes of a new heat-resistant suit for stuntmen. A All of them B 1 and 3 C 2 and 4 D 2 only Answer is B. I did C. Can you explain sir? I thought 1 and 3 are research costs.