Answer:
The answer is: Following the expected value criterion the investor should choose the sell strategy.
Explanation:
The formula we use to calculate the expected return value of the different strategies is:
      ERV = ∑ (expected return x probability of occurrence)
The buy strategy has an expected return value of of 1%
ERV Buy = (10% x 33.3%) + (1% x 33.3%) + (-8% x 33.3%) = 1%
The sell strategy has an expected return value of of 1.67%
ERV Sell = (6% x 33.3%) + (2% x 33.3%) + (-3% x 33.3%) = 1.67%