The Use of P=50%,q=50% Is a Research Industry Standard at Least

Multiple Choice

The use of p=50%,q=50% is a research industry standard at least in part because:

A) it is the most conservative p-q combination
B) it generates the largest sample size
C) it is preferred to guessing about variability
D) there may be little prior knowledge about the population to be studied
E) all of the above are true