Rationale
Breathe
A stuffy nose obstructs airflow through the nasal passages, making it difficult for a child to breathe comfortably. This nasal congestion can lead to an increased reliance on mouth breathing, which is less efficient and can cause further discomfort.
A) This option accurately reflects the difficulty a child experiences when their nose is congested. "Breathe" is the correct verb that describes the action of inhaling and exhaling air, which is compromised when the nasal passages are blocked.
B) "Breathing" is a gerund form of the verb and does not fit grammatically in the context of the sentence. The question asks for an action that is hard to perform, and "breathing" as a noun does not convey that meaning effectively.
C) While this option is the same as option A, it is a duplicate and does not provide a distinct choice. The correct action of inhaling is indeed represented here, but as a repeated option, it does not further clarify the answer.
D) "Breadth" refers to the width or extent of something but is unrelated to the context of nasal congestion and breathing difficulties. This option is not relevant to the situation and does not address the issue of a stuffy nose at all.
Conclusion
In summary, when a child experiences a stuffy nose, the most pertinent action affected is their ability to breathe, making option A the clear choice. The other options either misinterpret the required grammatical structure or fail to relate directly to the context of nasal obstruction, underscoring the importance of selecting the correct verb form in such scenarios.