Crime detection in a forensic laboratory involves the use of

Analyze the question: It asks what forensic laboratories use to detect crime, that is, to link a suspect to a crime scene or identify a victim.

Concept: Forensic science applies biology and other sciences to criminal investigation. Common tools include:

• Fingerprint analysis (dermatoglyphics), because ridge patterns are unique to each person and stay the same for life.
• DNA profiling, which is also called DNA fingerprinting.
• Blood typing and blood-stain analysis.
• Hair, saliva, and other body-fluid analysis.

Evaluating the options:

• A. Blood transfusion: This is a medical procedure for giving blood to patients. It is not a crime detection method.
• B. Blood analysis: This is used in forensics, since blood group and DNA from blood stains can point to a suspect. It is a plausible answer, but it is a broad category.
• C. Fingerprints: This is the classic and most widely recognized forensic tool. Each person's prints are unique and are left on surfaces at crime scenes.
• D. Genetic combination: This is a vague phrase about how genes combine. It is not a forensic technique.
• E. Tongue rolling ability: This is a simple inherited trait, shared by many people, so it cannot identify an individual.

Answer: The best choice is C. fingerprints. Blood analysis (B) is also used in forensics, but fingerprints are the standard answer for crime detection in this type of NECO question.

Exam tip: When a question links "crime detection" or "identification of individuals" with biology, think of fingerprints first, then DNA. Eliminate options that describe medical procedures or common traits shared by many people, such as tongue rolling.