Sahar's baby is 6 months old and teething.Sahar had the baby at a health care office for a 6-month checkup and Sahar is appropriately wearing a mask.The baby started to cry.What may be the cause of the baby crying?

Choice A rationaleBabies at around 6 months are developing object permanence and might experience anxiety if they cannot see familiar faces, such as their mother's due to the mask.Choice B rationaleHunger is a common cause of crying in infants but doesn't specifically relate to the scenario provided regarding the mask.Choice C rationaleCold can cause discomfort in infants, leading to crying, but this is more of a general response and not directly related to the mask scenario.Choice D rationaleStress can cause crying, but the specific trigger in the scenario is the mother's masked face, causing potential anxiety.