How can you best describe her grade in the Proficiency exam?

Describing her grade as "a good result even if lower than expected" captures the nuanced understanding of her performance. This statement acknowledges that while the outcome did not meet her expectations, it still falls within the realm of a "good result," implying that the performance was commendable, although it may have been overshadowed by personal goals. This allows for a perspective that recognizes both the achievement and the disappointment without undermining the overall positive nature of her results.

This choice effectively balances the acknowledgment of her effort and capabilities against the context of what she hoped to achieve, making it both realistic and supportive. The other options either portray the grade too negatively or positively without considering the complex feelings a student might have about performance in relation to their goals.