Ancient photosynthetic prokaryotes were very important in the history of life because theya. produced the oxygen in the atmosphere. b. are the oldest known archaea. c. were the first multicellular organisms. d. showed that life could evolve around deep-sea vents.

Option A.

Produced the oxygen in atmosphere

Explanation:

Photosynthetic prokaryotes have chlorophyll in their cytoplasm. The chlorophyll is join to protein to form chlorosome(light harvesting molecules) which in turn convert light energy to chemical energy and fixed carbon dioxide in the atmosphere by synthesizing light in sugar , thereby release oxygen to the atmosphere. The photosynthetic prokaryotes include cyanobacteria, algae e.t.c

answer: angiosperms

dicots

angiosperms are highly evolved plants, they produce seeds which are enclosed within in a carple. these are the largest group of plants on earth. they include trees, shrubs, herbs and small flowering plants. angiosperms exhibit a flowering stage in their life cycle. the flower serves the function of reproduction and fruit formation in majority of angiosperms. dicot is the term used to describe flowering plants that have two seed leaves. dicots are plants which develop seeds which split into two parts called cotyledons. each cotyledon contains one embryo.

here, a small purple flower development indicates that the plant belongs to angiosperms and having two embryonic leaves indicates it belongs to dicots.