- The correct answer is: Centromere positioned at the center.

- A metacentric chromosome is characterized by having its centromere located approximately at the middle of the chromosome, resulting in two arms of roughly equal length. This symmetrical arrangement distinguishes metacentric chromosomes from other types such as submetacentric or acrocentric chromosomes, where the centromere is positioned off-center, leading to arms of unequal lengths.

- Option 1 correctly identifies the centromere position in a metacentric chromosome.
- Option 2 describes an acrocentric or telocentric chromosome where the centromere is near one end.
- Option 3 is incorrect as centromeres are essential for chromosome movement during cell division.
- Option 4 refers more to a submetacentric chromosome, where the centromere is off-centered but not at the very end.

Reference: “Principles of Genetics,” 8th Edition, Snustad & Simmons, Chapter 4, p. 85-86.