Which of the following pathologic conditions are considered additive conditions?

Additive conditions refer to pathological states that increase the radiographic density of the tissues involved, resulting in an increased absorption of X-rays on imaging. This requires an adjustment in technical factors during imaging, such as increasing the mAs or kVp, to accurately portray the anatomy and pathology of interest.

In this case, each of the conditions listed—osteoma, bronchiectasis, and pneumonia—results in increased density due to the presence of additional material or thickening of the structures. Osteomas are benign tumors that can increase the density of the bone. Bronchiectasis involves the chronic dilation and infection of the bronchi, leading to increased lung density. Pneumonia causes inflammation and fluid accumulation in the lung tissue, further increasing density.

Since all the conditions mentioned lead to an additive effect on imaging, the option that states all of the above being additive conditions is correct as they all exhibit similar characteristics that require consideration during image acquisition.