Final answer:
E.B. White is suggesting that the best time to become a father is 18 years after a specific event.
Step-by-step explanation:
In this quote, E.B. White is referring to the responsibility and challenges of becoming a parent. He suggests that the best time to become a father is 18 years after certain event.
The correct answer is Marriage. White is implying that it is best to become a father 18 years after getting married, as it allows for more time to mature and prepare for the role of parenthood.