Final answer:
Carmakers in Europe have faced challenges due to their dependence on diesel for several reasons: higher emissions, stricter regulations, and loss of consumer trust.
Step-by-step explanation:
Carmakers in Europe have faced challenges due to their dependence on diesel for several reasons. First, diesel engines have come under scrutiny for their higher emissions of particulate matter, which contributes to air pollution and health problems. As a result, there has been a shift in consumer preference towards cleaner fuel alternatives such as electric vehicles. Second, stricter environmental regulations and emission standards have been introduced in Europe, making it more difficult for carmakers to meet these requirements with diesel engines. Finally, the Dieselgate scandal, where Volkswagen was found to have cheated on emissions tests, damaged the reputation of diesel and eroded consumer trust in diesel-powered cars.