Nope, that makes it FAR worse
And in any case, that isn't the 'convention' - it's equally 'correct' either way, mostly based on the era in question - this is a (very poorly written) very old question, from back when almost all transistors were PNP, and so the chassis was positive.
As I've said in these forums many times, it makes far more sense to ignore negative and positive, and just think of high or low - so for a positive earth circuit (like this one) negative 8 volts is higher than ground.
But in any case, the question is very poorly written, makes no real sense, and whoever wrote it wants taking out and flogging - except they are probably long dead, and (as was common among exam question setters) probably had no electronic knowledge anyway (often they were supposedly written by English teachers).