Which of the following factors can cause right axis deviation?

Right axis deviation occurs when the electrical activity of the heart is oriented more toward the right side of the body. This typically happens due to various cardiac conditions that lead to changes in the structure or function of the heart.

The choice that cites right infarction and left hypertrophy is relevant because right-sided heart strain or overload can cause an increase in right ventricular size or hypertrophy, which shifts the electrical axis toward the right. Additionally, left ventricular hypertrophy can result in leftward axis shifts; however, when occurring alongside conditions that primarily affect the right side of the heart, such as right-sided infarctions, the net effect can lead to a right axis deviation. Essentially, during a right-sided myocardial infarction, the right ventricle's workload increases, subsequently altering the heart's electrical axis in a rightward direction.

In contrast, while other options mention conditions like chronic lung disease or heart failure, these do not necessarily cause a right axis deviation in the same direct manner as right infarction and left hypertrophy do. Some conditions may also have mixed effects on heart position or axis without a definitive rightward shift. Thus, the choice linking right-sided issues with left ventricular hypertrophy provides a clear pathway to understand why right axis deviation would be the resultant