What type of devices are typically used for manipulations in controlled environments?

The correct choice highlights the importance of specialized equipment used for maintaining specific environmental conditions while conducting experiments or handling laboratory animals. Hoods or laminar flow cabinets are designed to protect both the samples and the operator by providing a controlled airflow that minimizes contamination and ensures a sterile environment.

These devices are essential in controlling variables such as air quality, temperature, and microbial contamination, which are critical for research integrity and animal welfare. They create an environment that is conducive to accurate data collection and the health of the organisms involved in the research.

While air conditioners and refrigerators play essential roles in controlling temperature, they do not provide the level of contamination control necessary for sensitive manipulations. Incubators are important for specific applications involving growth and development of biological entities but lack the airflow and contamination prevention features of laminar flow cabinets, making them less suitable for handling of materials that require strict aseptic techniques.