Marsh pic has made a public announcement that it intends to introduce a new product which will decrease the beta of the firm. On the same day, River pic has publicly announced that it is being sued by a major customer for a batch of faulty goods.

If neither of these items of information had been made public before, what effect should they have on the companies share prices, assuming the stock market on which they are traded is semi$-$strong efficient?

Marsh pic

River pic

$$ A Decrease No change

OB$.$ Decrease Decrease

OC$.$ Increase

No change

$$

$$ D$.$ Increase

Decrease