What is the best fuel efficient engine option for a Ford Fiesta?

I am looking to purchase a Ford Fiesta and I want to make sure I choose an engine option that is both fuel efficient and powerful. Which engine option would you recommend and why?

I highly recommend the EcoBoost engine for the Ford Fiesta. It offers a great balance of power and fuel efficiency.

I have found the 1.0L engine to be the most fuel efficient, but it may lack the power you are looking for.

Personally, I would go with the 1.6L engine. It's a bit less fuel efficient, but it offers a good amount of power and torque for a small car.