Final answer:
Flying insects do have a high metabolic rate when flying and can produce as much heat as endotherms.
Step-by-step explanation:
Insects have a high metabolic rate when flying and can produce as much heat as endotherms. This statement is true. When insects are in flight, their muscles are working at a higher intensity and speed, which leads to an increased metabolic rate. This metabolic energy is released as heat, similar to how endotherms (animals that regulate their body temperature) generate heat.