You are answering a USMLE-style medical question. Question: A 59-year-old woman presents to the outpatient clinic for worsening symptoms of congestive heart failure. She states that while she used to be able to go for short walks, she is no longer able to do so. Now, even simple tasks like getting ready in the morning have become burdensome for her. When she gets tired, sitting down helps to alleviate her symptoms. Her blood pressure is 136/92 mm Hg and heart rate is 76/min. On physical examination, she has regular heart sounds but does have 1+ pitting edema to her bilateral lower extremities. What is her New York Heart Association Functional Classification for congestive heart failure? Options: A) New York Heart Association Class IIa B) New York Heart Association Class IIb C) New York Heart Association Class III D) New York Heart Association Class IV Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.