निम्नलिखित में से कौन सा समूह पूरी तरह से एककोशिकीय जीवों का है?

The main criteria used for Five Kingdom Classification proposed by R.H. Whittaker (1969) included: A. Cell structure B. Body organization C. Presence of flagellum D. Reproduction E. Phylogenetic relationships Choose the correct answer from the options given below:

In which one of the following organisms are the ovules not enclosed by an ovary wall and remain exposed?