💡 Detailed Explanation
The correct choice is Option 3: 'Spend 15 minutes of free time.' The guide announces: 'これからバスに乗ってホテルへ向かいますが、その前に15分間の自由時間を取ります' (We will head to the hotel by bus now, but before that, we will take a 15-minute free time). During this free time, they can buy souvenirs or use the restroom at their own discretion. Therefore, the immediate overarching phase they enter is the free time ('自由時間を過ごす'), making Option 3 the correct comprehensive action.