Read the following statements related to pteridophytes.
i) They are the first terrestrial plants to possess vascular tissue.
ii) Pteridophytes are found in cool, damp, shady places. Some of them may flourish in sandy soil conditions.
iii) Prothallus require cool, damp, shady places to grow.
iv) Water is not required for the transfer of antherozoides.
v) Majority of pteridophytes are heterosporous.
vi) Dryopteris belongs to class sphenopsida.
How many statements are incorrect?