To fill in the blanks in the passage:

1. For the first blank, the best option is **B. attraction**. The sentence would read: "To make the most of this exciting **attraction** in the city..."

2. For the second blank, **B. station** fits well. The sentence would be: "First, find a nearby **station** where the bus stops..."

3. For the third blank, **B. ticket machine** is appropriate. The sentence would then read: "Next, purchase your ticket from the **ticket machine**..."

4. Finally, for the fourth blank, **A. upper** is the best choice. The completed sentence would be: "Finally, board the bus and find a comfortable seat on either the **upper** deck..."

So, the completed passage reads:

"Welcome to Hanoi’s new double-decker bus service! To make the most of this exciting **attraction** in the city, follow these simple steps. First, find a nearby **station** where the bus stops; you can check the schedule online or at the station. Next, purchase your ticket from the **ticket machine** or use a contactless payment option. Finally, board the bus and find a comfortable seat on either the **upper** deck. Enjoy your ride and explore the beautiful city of Hanoi!"