Exam question asking how 'spontaneous human combustion' is 'impossible'!

What do you think of this? Is this unprofessional on the educational system's side?

My son has a practice exam paper he brought home a couple of weeks ago, and I was appalled:

Here it is: '''' ' Breaking apart a molecule through combination of oxygen is burning and is also how we measure the energy content of the chemical bonds, in calories using a calorimeter. However, cell metabolism is a ''slow burn''. Write the reason why rapid direct oxidation cannot naturally occur in the cell environment-that is, why ''spontaneous human combustion'' is not possible. '''

Are biased questions such as this commonplace in science papers? How is such a wrongful statement even allowed? There have been many cases of SHC. It is far from 'impossible' and very disgraceful to the families affected.