Read the short story.

One afternoon, Billy's father decided it was time to teach his young son how to ride a bicycle. The two headed out to the driveway after lunch. Billy's father removed Billy's training wheels and made sure the boy's helmet was fastened tightly. Then he held the bike while Billy tried to balance. Billy tried to balance and pedal at the same time. He just couldn't seem to get it. By one o'clock, Billy had two skinned knees and a bruised elbow.

Which conclusion would readers find most engaging?

After a few more tries, Billy's father gives up. He drags the old, red wagon out of the garage and pulls Billy up and down the driveway instead.
On Billy's last attempt, he crashes into a nearby tree, falls off his bike, and breaks his arm. Billy and his father spend the rest of the day in the hospital.
Billy's brother sees what is going on from his bedroom window. He heads outside and gives Billy a tip about keeping his chin up. Soon, Billy is riding with ease.
Billy gets frustrated and starts to cry. He pushes his bike down on the lawn and throws his helmet off. Then he tells his father that he doesn't want to learn how to ride a bike.

Readers would find the conclusion most engaging where Billy's brother sees what is going on from his bedroom window, comes outside, and gives Billy a tip about keeping his chin up. Soon, Billy is riding with ease.

The most engaging conclusion for readers would be:

Billy's brother sees what is going on from his bedroom window. He heads outside and gives Billy a tip about keeping his chin up. Soon, Billy is riding with ease.

Conclusion: Billy's brother sees what is going on from his bedroom window. He heads outside and gives Billy a tip about keeping his chin up. Soon, Billy is riding with ease.

To determine the most engaging conclusion, we need to consider which ending creates the most interest and leaves the reader curious or satisfied. In this case, the conclusion where Billy's brother offers a helpful tip and Billy successfully learns to ride a bike is the most engaging. This ending provides a sense of resolution and shows how a small piece of advice can make a significant difference.