A viral infection that may cause obstruction of the upper airway in a child is called: C. croup.
What is a virus?
In Biology, a virus can be defined as a small infectious parasite that is highly dependent on living cells of host organisms such as animals, bacteria or plants, for its replication (reproduction).
In Medicine, croup simply refers to a viral infection or virus-induced respiratory tract illness that is mainly responsible for the swelling of a child's airway, which eventually leads to an obstruction of the upper airway in a child.
In this context, we can reasonably infer and logically deduce that croup is a viral respiratory tract illness that typically occurs in children and it causes obstruction of the upper airway.
Read more on a virus here: brainly.com/question/15086177
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