Which of the following is NOT used as an alerting device for hearing-impaired people?

The correct answer is based on the understanding that all the devices mentioned are, in fact, used as alerting devices for hearing-impaired individuals. Flashlights and strobe lights are commonly utilized for visual alerts, as they can attract attention through bright lights when a sound occurs, such as a doorbell or fire alarm.

Transducers that shake beds or pillows serve as a tactile alert system, providing vibrations for notifications, which is particularly useful during nighttime or when a person may not be visually aware of their surroundings.

Trained hearing ear dogs are also invaluable, as they are trained to alert individuals to specific sounds, like alarms or a person's name being called, by providing physical cues, such as nudging.

Since all the mentioned devices serve the purpose of alerting hearing-impaired individuals to important sounds in their environment, the statement that "all of the above" are not alerting devices is not correct. Thus, identifying them as alerting devices emphasizes their critical roles in enhancing the safety and awareness of individuals with hearing impairments.