Answer: Express ratification
Explanation: The scenario above, is an example of express ratification. At the age of 17, Kendall lacked the contractual capacity at the time in which she entered an agreement with Harley Davidson. However, when she turn 18 and now has the contractual capacity, she can expressly inform Harley Davidson if she wants to be bound by the contract which is what Kendall did by sending an email, stating her desire to being bound by the agreement and continue making her monthly payment