A Company That Processes Wheat Varies the Milling Time (Short

A company that processes wheat varies the milling time (short, medium and long) and bleaching (no bleaching and bleaching) and measure fiber content (gms/100 grams) of the resulting wheat product to determine the best combination for a desirable wheat product.Which of the following is true about this study?

A) It is an observational study.
B) It is a completely randomized design in one factor.
C) The different levels of milling time act as blocks in the design.
D) It is an experimental study.
E) The different level of bleaching act as blocks in the design.