Answer:
A) according to put call parity:
price of put option = call option - stock price + [future value / (1 + risk free rate)ⁿ]
put = $8.89 - $120 + [$120 / (1 + 8%)¹/⁴] = $8.89 - $120 +$117.71 = $6.60
B) you have to purchase both a put and call option ⇒ straddle
the total cost of the investment = $8.89 + $6.60 = $15.496, this way you can make a profit if the stock price increases higher than $120 + $6.60 = $126.60 or decreases below than $120 - $6.60 = $113.40