You want to buy 100 shares of XYZ stock, and you don't want to pay more than $20 per share for it. Which option strategy would be the least expensive?
a) Buy one XYZ 20 call for $2
b) Sell one XYZ 20 call for $4
c) Buy one XYZ 20 put for $1
d) Sell one XYZ 20 put for $3