Which of the following road users are likely to take an unusual course at roundabouts?

Horse riders are likely to take an unusual course at roundabouts for several reasons related to their unique mode of transport. Horses can be unpredictable and may not respond in the same way as motorized vehicles or cyclists. When navigating roundabouts, horse riders must account for their horse's behavior, which can include sudden starts or stops, as well as potential spookiness caused by traffic or the environment.

Additionally, horse riders often need to take a wider line when turning to maintain control and ensure their safety. This can result in deviating from the standard path that vehicles follow, making them appear to take an unusual course compared to other road users. Furthermore, the nature of riding a horse means that riders may prioritize safety over speed, leading to slower and more variable speeds while at roundabouts, further contributing to the likelihood of taking a course that differs from more conventional vehicles.