Explain the differences among the completely randomized design, randomized complete block designs, and factorial design. Choose the correct answer below.

O A. In a completely randomized design, the researcher examines a single factor and randomly distributes experimental units. In a randomized complete block design, the researcher partitions experimental units according to two fixed factors, factor A and factor B. In a factorial design, the researcher has a factor whose level cannot be fixed.
O B. In a completely randomized design, the researcher examines many factors and randomly distributes experimental units. In a randomized complete block design, the researcher partitions experimental units according to two fixed factors, factor A and factor B. In a factorial design, the researcher has a factor whose level cannot be fixed.
O C. In a completely randomized design, the researcher examines a single factor and randomly distributes experimental units. In a randomized complete block design, the researcher partitions experimental units according to a factor whose level cannot be fixed. In a factorial design, the researcher has two fixed factors, factor A and factor B.
O D. In a completely randomized design, the researcher examines a random factor and randomly distributes experimental units. In a randomized complete block design, the researcher partitions experimental units according to a factor whose level is fixed. In a factorial design, the researcher has two fixed factors, factor A and factor B.