ASIS Professional Certified Investigator Practice Exam 2026 – Complete Study Guide

The correct answer focuses on the nature of Restriction Fragment Length Polymorphism (RFLP) analysis. RFLP is a technique used in genetics to analyze the variations in DNA sequences. It does this by cutting DNA into pieces with restriction enzymes and then separating those pieces via gel electrophoresis. Through this process, RFLP helps researchers identify genetic differences among individuals by showing variations in the lengths of DNA fragments. This method does not merely eliminate genetic possibilities; it identifies specific variations and can assist in determining genetic relationships or mapping genes.

Regarding the other statements, it's important to clarify why they are not considered correct. While polymerase chain reaction (PCR) is a powerful tool for amplifying DNA, it does not inherently "positively identify" a specific DNA sequence without additional context or comparison to known sequences. The idea that polymorphisms are irrelevant is incorrect as polymorphisms, or variations in the DNA sequence, are actually crucial for understanding genetic diversity and the function of genes. Finally, the statement that all genes are identical among humans is also incorrect because humans exhibit significant genetic variation, with the majority of genes having some differences across individuals, which contributes to the diversity seen in traits and susceptibility to diseases.