Austin reached into his backpack to make sure that it was there. He wasn’t sure he needed his inhaler, but he was checking just in case. His chest was tight as he once again attempted a deep breath. He completely filled his lungs and exhaled smoothly. He repeated this rhythm several times, surprised at the ease at which it came. But he’d keep the inhaler in his pocket. It had been a long time since he’d had a real asthma attack, since Little League, in fact. But it was never too far from his mind, especially when he played baseball.
From the fact that Austin's checks his breath in paragraph 1, we can conclude that he is

A) determined.
B) distracted.
C) lighthearted.
D) worried.