Concept:High relative humidity means excess moisture in the air, which creates damp conditions inside the brooder house.
Explanation:When relative humidity is high, the air holds a large amount of water vapour.
This moisture settles on the litter and makes it wet and damp.
Damp litter provides an ideal environment for pests, fungi, moulds, and disease-causing micro-organisms to grow and multiply rapidly.
As these organisms build up, the chicks become more prone to infections and disease outbreaks.
High humidity does not directly reduce feed intake, nor does it produce dry litter; in fact, it makes the litter wetter.
Heat stress is mainly associated with high temperature rather than high humidity alone.
Therefore, the most likely consequence of high relative humidity in a brooder house is an increase in pests and diseases.
Answer:C. Build up of pests and diseases