Which of the following is not a semisynthetic polymer?

semisynthetic polymer are those which are obtained from nature and used and applied after modification but cis-polyisoprene is completely synthetic polymer, and synthetic polymers are Human made therefore, option (i) is the correct answer.

Cellulose nitrate, cellulose acetate, vulcanised rubber are semisynthetic polymers therefore options (ii),(iii),(iv) are incorrect.