Five jumbled up sentences (labelled 1, 2, 3, 4 and 5), related to a topic, are given below. Four of them can be put together to form a coherent paragr...

Five jumbled up sentences (labelled 1, 2, 3, 4 and 5), related to a topic, are given below. Four of them can be put together to form a coherent paragraph. Identify the odd sentence and key in the number of that sentence as your answer.

$1.$Urbanites also have more and better options for getting around: Uber is ubiquitous; easy-to-rent dockless bicycles are spreading; battery-powered scooters will be next.

$2.$ When more people use buses or trains the service usually improves because public-transport agencies run more buses and trains.

$3.$ Worsening services on public transport, terrorist attacks in some urban metros and a rise in fares have been blamed for this trend.

$4.$ It seems more likely that public transport is being squeezed structurally as people's need to travel is diminishing as a result of smartphones, video-conferencing, online shopping and so on.

$5.$ There has been a puzzling decline in the use of urban public transport in many countries in the west, despite the growth in urban populations and rising employment.