What is required for each instar stage of bed bugs?

The correct answer is that each instar stage of bed bugs requires a blood meal. Bed bugs undergo several stages of development known as instars, and they must feed on blood to grow and molt from one stage to the next. This feeding is essential because bed bugs rely on the nutrients found in blood to sustain their growth and reproductive processes.

During their lifecycle, bed bugs typically pass through five instars before reaching maturity. At each stage, they shed their exoskeleton in a process known as molting, which only occurs after they have ingested a sufficient blood meal. Without this critical nourishment, they cannot progress to the next instar, which highlights the importance of blood meals in their development.

While food and moisture, an egg sac, and temperature are important factors in the general biology and habitat preferences of bed bugs, they do not directly contribute to the specific requirements for progressing through instars. Blood meals are explicitly necessary for the growth and development cycle of bed bugs, making it the key requirement in this context.