What is a common cause of hyperglycemia?

B. Insufficient insulin or medication is a common cause of hyperglycemia because when the body does not have enough insulin to facilitate the uptake of glucose into the cells, blood sugar levels can rise significantly. Insulin is crucial for regulating blood glucose levels; without sufficient insulin, glucose remains in the bloodstream instead of being utilized by the body's cells for energy, leading to hyperglycemia.

Inadequate medication adherence or dosage can lead to glycemic control issues, particularly for individuals dependent on insulin or other glucose-lowering medications. This can occur during illness, stress, or if there has been a recent change in diet or activity level that is not adequately accounted for with medication adjustments.

Other potential causes listed do not typically lead to hyperglycemia in the same way. Excessive exercise usually lowers blood sugar levels, while low carbohydrate intake also tends to decrease blood sugar levels. Dehydration can impact blood sugar levels as well, but it does not directly cause hyperglycemia the way insufficient insulin or medication does. Thus, a lack of enough insulin or diabetes medication is a key factor in hyperglycemic episodes.