The correct option is A If both the assertion and the reason are true and the reason is a correct explanation of the assertion
On the basis of
(i) Thallus like non-vascular plant body,
(it) Simple, unicellular non-jacketed sex organs and
(iii) No embryo development after gametic union, the algae and fungi have long been grouped together in thallophyte. The algae and fungi are the result of parallel development and do not indicate any phylogenetic relationship.