Final answer:
The fungi that do not undergo sexual reproduction were traditionally called 'imperfect fungi'; however, with modern molecular techniques, these fungi are categorized within Ascomycota or Basidiomycota.
Step-by-step explanation:
The fungi that do not reproduce sexually were traditionally classified as imperfect fungi. These organisms, which lack a known sexual phase of reproduction, were once placed in a separate group called the Deuteromycetes or sometimes Fungi Imperfecti. However, this is an outdated classification. Nowadays, with advances in molecular biology, these fungi are often reclassified into other fungal groups, typically within the Ascomycota or Basidiomycota.
Techniques such as DNA sequencing have made it possible to place these 'imperfect' fungi into their proper phylogenetic categories, often incorporating them into the Ascomycota or Basidiomycota phyla, making the term Deuteromycota obsolete.
The answer to the question is thus: a) Imperfect fungi