Final answer:
In terms of complexity, mosses are the simplest, followed by ferns, then conifers, with flowering plants being the most complex. These types of plants represent different stages of plant evolution, each showing increased complexity.
Step-by-step explanation:
The plants you mention—mosses, ferns, conifers, and flowering plants—represent different stages of plant evolution, with each demonstrating increasing complexity. The simplest are the mosses, which were the first plants to colonize land about 500 million years ago and lack true leaves and roots. Ferns are the next most complex. They are the most advanced seedless vascular plants and developed large fronds, though they still reproduce via spores rather than seeds. Conifers are more complex than ferns as they have seed-bearing cones, allowing them to reproduce without requiring water for the sperm to reach the egg. The most complex of these are the flowering plants as they have further specialized structures such as flowers and fruit to aid in reproduction. So, the order from simplest to most complex would be: mosses, ferns, conifers, flowering plants.
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