sabella accidently overheard that the CFO was talking to the CEO about the business expansion plan for her company. She thinks that she can make a huge gain if she immediately purchases the companys shares. If Isabella is right, which efficient market hypothesis is observed in this case? (There may be more than one correct answer. You will lose marks by choosing a wrong answer. The minimum mark for the question is zero.)

Select one or more:

a. Weak form

b. Informational efficiency

c. Operational efficiency

d. Semi-strong form

e. Strong form