Translation:The ambulance took my husband to the hospital.
At least in British English, if you are a patient going to hospital for treatment, then you are "taken to hospital". Similarly, children go to school, they may go to church on Sundays, you go to bed at night and you can be sent to prison. None of these examples use the definite article, in English. However, if you go to visit someone in hospital then you would be "taken to the hospital". Similarly, a parent would go to the school to speak to their child's teacher, a laundry van would take clean sheets to the prison, etc. In Spanish, this distinction is not made and the definite article must be used in all cases - so Portuguese is likely to be the same Both options should be accepted as correct in English; another case of being marked "wrong" by duolingo, even though my sentence would actually be the default translation (why: because if you are taken by ambulance, then you are likely to be a patient, so "taken to hospital" is much more likely - at least for British English)