Which of the following molds is an example of mesophilic molds?

Mesophilic molds thrive in moderate temperature ranges, typically between 20°C and 45°C (68°F and 113°F). Aspergillus is a genus of molds that is well-known for its prevalence in various environments and its ability to grow within this temperature range. This adaptability makes Aspergillus one of the most commonly encountered molds in indoor and outdoor settings.

The other options represent different characteristics of molds or organisms. Thermophilus, for instance, is indicative of molds that grow optimally at higher temperatures, generally above 45°C. Chlorella is primarily a type of green algae that grows in freshwater and is not classified as a mold. Cryptococcus, while being a yeast that can cause infections, is not classified under mesophilic molds either, as it has different growth requirements and does not primarily thrive in that specific temperature range. Hence, Aspergillus stands out as the correct choice, exemplifying the features of mesophilic molds.