Not Sure Validation Engineer interview questions

Applied the job through a recruiter for a big pharmaceutical company. Interviewer asked a lot of technical questions related to R&D industries and I couldn't give the answer he was seeking for due to my lack of experience and knowledge in that aspect as I'm a fresh graduate. It's understandable that he asked all the technical questions and I'm not blaming him for that. However, would complain about the recruiter as he pretended to give support and all but all he didn't really hide the fact that he was doing this just for the commission. Recruiter listed the range of salary that the employer gives and asked if my expected salary was negotiable eventhough I've asked for a lesser than average amount.