A Professor at a University Finds a Way to Reduce

Multiple Choice

A professor at a university finds a way to reduce the costs of producing automobile glass.The method is very easy for anyone to copy.A company develops a substance which prevents eyeglasses from smudging.It receives a patent on the formula.Which of these are common technological knowledge?

A) the method to reduce costs of producing automobile glass,and the formula for the substance that prevents smudging
B) the method to reduce costs of producing automobile glass,but not the formula for the substance that prevents smudging
C) the formula for the substance that prevents smudging,but not the method to reduce costs of producing automobile glass
D) neither the method to reduce costs of producing automobile glass nor the formula for the substance that prevents smudging