Which is the most important group on earth?

The correct option is B Tracheophyta
Tracheophytes are vascular plants with roots, stem and leaves. Some tracheophytes reproduce with seeds and some reproduce with spores. They possess conducting or vascular tissues, xylem and phloem. There are 275,000 living species of tracheophytes. They are the source of food, fibres, fuel, furniture, medicines and are considered as an important group of plant on earth.

So, the correct answer is option 'Tracheophyta'.