Why is it important to start saving for retirement decades before retirement age?

It is important to start saving for retirement decades before retirement age because of compound interest. When you start saving at a younger age, you have more time for your money to compound. In other words, you can start with a smaller amount of money and after 30 years of compounding, it can grow to a larger amount.

Compounding is the formula 1 + r to the n which means interest compounds into more interest over time.

the answer is d. 75%