The heterosporous pteridophytes are

The correct answer is Option (3) - Selaginella and Salvinia.

Heterospory is the production of spores of two different sizes and of two different developmental patterns - smaller male or microspores and larger female or megaspores.

Heterospory is the most important evolutionary development in the vascular plants because it has ultimately led to seed development e.g. Selaginella, Salvinia, Azolla, etc.

Most of the pteridophytes are homosporous and produce only one kind of spore. But very few pteridophytes like Selaginella and Salvinia are heterosporous. Pteris, Adiantum and Dryopteris are homosporous.