I believe I am the first one to reply here but please feel free to chime in in case i missed a crucial point.
This was a relatively simple passage maybe sub-600.
Here's my mind map & rationale.
Para1: Author discusses some paramount medical problem. Explains the reason for it and later says that recent research has helped in a part of the problem but some challenges still persist.
1. According to the passage, the major problem currently facing scientists in the field of biomaterials is(A) assessing and regulating the bonding between host tissue and implants
Straightforward quote from line 3 & 4 (B) controlling the transfer of potentially toxic materials across the interface of tissue and implant
(C) discovering new materials from which to construct implant devices
(D) deciding in what situations implants are needed
(E) determining the importance of short-term implants to long-term stability of tissue-implant interfaces
2. The passage suggests which of the following about the recent research (Text in Blue)?(A) It has solved one set of problems but has created another.
The passage does not say that new research created new problems(B) It has concentrated on secondary concerns but has ignored primary concerns.
Tempting. But from the highlighted text we don't know what's primary and what's secondary(C) It has improved practical applications of biomaterial technology without providing a complete theoretical explanation of that improvement.
Seems correct. Because new research "stabilized the tissue-biomaterial interface" (improved practical applications), but our fundamentals still remain unclear (theoretical explanation) (D) It has thoroughly investigated properties of biomaterials but has paid little attention to relevant characteristics of human tissue.
Out of scope(E) It has provided considerable information on short-term implant technology but little on long-term implant technology.
OOS 3. The author’s primary purpose is to(A) answer a theoretical question in the field of biomaterials
180 degree. The passage even till the end is unable to answer the fundamental question(B) discuss the current state of technology in the field of biomaterials
Correct(C) resolve a research dispute in the field of biomaterial
There is no dispute in the first place(D) predict an ethical crisis for biomaterials researchers
OOS(E) suggest some practical benefits of biomaterial implants
OOS