Question regarding market efficiency?

Question

If share prices do not adjust to publicly available new information rapidly such that excess returns can be earned by trading on that information, the market is displaying ?

a. Weak-form efficiency

b. Semi-strong form efficiency

c. Strong-form efficiency

d. None of the above

Answer 1

a. Weak-form efficiency

The weakest form states that prices reflect all information consisting of past prices (thus does not include currently publicly available informations which are INSTANTANEOUSLY reflected in the semi-strong form).