<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A randomized, controlled trial was undertaken by a team of clinical researchers to evaluate a new drug for the treatment of cluster headaches. This type of headache that mostly affects men is characterized by excruciating pain on 1 side of the head. After careful randomization and controlling for all of the known confounders, a total of 200 patients with cluster headaches were divided into 2 groups. The first group of study participants received 40 mg of the new drug, X, in the form of a powder mixed with water. The second group received 80 mg of verapamil a calcium channel blocker that is commonly prescribed for cluster headaches in the form of a labeled pill. Participants from both groups were mixed together in rooms designated for drug research purposes and could communicate freely. After the study period has finished without any loss to follow-up or skipped treatments, the outcome pain alleviation was assessed by trained researchers that were blinded to treatment assignment. Study results have shown that the new drug is more efficacious than current gold standard by both clinically and statistically significant margin. Therefore, the investigators concluded that this drug should be introduced for the treatment of cluster headaches. However, their conclusions are likely to be criticized on the grounds of which of the following?? A: Observer bias, B: Response bias, C: Convenience sampling bias, D: Attrition bias, E: Intention to treat bias,  <response>: This is a randomized controlled trial comparing a new drug X to the standard treatment verapamil for cluster headaches. The question asks us to identify a potential criticism of the study conclusions based on the study design. The choices present different types of biases.The study appears to be well-designed overall - it is randomized, controlled, blinded, and uses intention to treat analysis with no loss to follow-up. However, one design issue is that the participants from the two treatment groups were mixed together during the study. This could potentially lead to response bias, as participants may influence each others responses or reporting of outcomes. The other answer choices do not seem to apply based on the information provided:- Observer bias is unlikely since outcomes were assessed by blinded researchers - Convenience sampling bias is not mentioned - Attrition bias is not a concern since there was no loss to follow-up- Intention to treat analysis was used, so that bias should be minimizedB: Response bias 