Great responses so far!
I think the simple, direct answer to the specific original question, is B - "compressor blades".
..but for fun, I'll add a bit of detail too....
With high bypass turbine engines, in the few percent of cases where a bird is ingested through the core (in my own experience, I'd guess that to be around 10% of ingestion incidents), after the fan, the bird first meets the Low Pressure (LP) compressor. (Sometimes referred to as the "booster" section). The interruption to airflow, though potentially problematic and/or itself damaging, is probably not as worrisome as the potential for damage by breaking some of the LP compressor blades, whose bits would then carry on downstream, possibly causing much damage to later stages of compressor...
I'd offer a rough estimate/educated guess that about half of those engines unfortunate enough to ingest a bird into their core, will have suffered enough damage to warrant removal.
Much is dependent on bird size, and engine speed.
In any core ingestion event, a boroscope is necessary... often damage has been caused, in the form of bent tips and corners, or small tears and even missing pieces, of compressor blades... As I said, I'd guess half the time the damage is all found to be within limits, but necessitating a more frequent boroscope schedule to monitor for further deterioration.
Cases, such as Sully's, where bird ingestion immediately renders the engine U/S, are relatively few and often include either very large, or very many birds.
Lomapaseo, I love your last statement! Great attitude! .... Learning something only requires an open mind... In my attempts to add something, I hereby offer my apologies for any incorrect info I may provide, and I hope I can learn with humility.
