Which of the following is a common gastrointestinal complication of enteral feedings?

Constipation is indeed a common gastrointestinal complication associated with enteral feedings. This can occur due to several factors, including the composition of the enteral formula, insufficient fluid intake, and lack of dietary fiber in the feeding. Enteral nutrition is often rich in calories and may not provide adequate amounts of fiber unless specifically designed to do so, which can lead to reduced bowel motility and harder stools, ultimately resulting in constipation.

In contrast, dehydration is often a result of inadequate fluid intake and can occur in various situations, including when enteral feedings are not accompanied by appropriate hydration measures. Hyperglycemia may occur in patients receiving enteral nutrition, particularly if they have underlying conditions such as diabetes, but it is not as uniformly associated with enteral feedings as constipation is. Rapid weight gain may happen as a response to overfeeding or inappropriate nutritional management but does not specifically highlight a gastrointestinal complication like constipation does. Therefore, constipation is a direct consequence of the gastrointestinal system's response to enteral nutrition, making it the most suitable answer in this context.