The correct answer is D. it uses imperfect coordinating structure.
Parallelism refers to the use of the same word form throughout a particular sentence. So, in the example above, in order to achieve parallelism, we would need to change the word 'vacuuming' into 'to vacuum,' in order to keep the consistency with the other two verbs: 'to dust' and '(to) straighten up.'
Answer:
I'd rather know when I'm going to die, since death is inevitable for humans.
So I'd just prepare for that day, whereas, knowing how I'll die would just make me more frightened in daily life, since I wouldn't know when I would die (unless it's by old age).
