Question

The region of a chromosome to which spindle fiber is attached is
A) Centriole
B) Chromomeres
C) Centromere
D) Chromocenter

Answer 1

Hint: 1) Chromosomes are thread-like proteins that exist within the nucleus of animal and plant cells.
2) Each chromosome is composed of protein and one molecule of deoxyribonucleic acid (DNA).
3) DNA, which is passed on from parents to offspring, includes the basic instructions that distinguish each form of the living organism.

Complete answer
Mitosis is a stage of the cell cycle during which replicated chromosomes are split into two new nuclei. During mitosis prophase, specialized regions on centromeres known as kinetochores bind chromosomes to spindle fibers. The centromere is a chromosomal region that connects sister chromatids. Spindle fibers attach to the centromere through the kinetochore during mitosis. Kinetochore fibers are formed by kinetochores, which attach sister chromatids to spindle fibers. During mitosis and meiosis, kinetochore fibers and spindle polar fibers collaborate to regulate and divide chromosomes.
Here option A is centriole. Centrioles are paired barrel-shaped organelles found near the nuclear envelope in the cytoplasm of animal cells. Centrioles aid in the organization of microtubules, which act as the cell's skeleton structure. They are not attached to chromosomes in any way.Hence, option A is incorrect
Option B is chromomere. A chromomere, also known as an idiomere, is one of the serially aligned beads or granules of a eukaryotic chromosome, resulting from the local coiling of a continuous DNA thread. Hence, this is also the wrong option.
Option C is centromere. A centromere is a specialized DNA sequence on a chromosome that connects two sister chromatids (a dyad). Spindle fibers attach to the centromere through the kinetochore during mitosis. Centromeres were originally believed to be genetic loci that direct chromosome action. Hence. this is the correct option
Option D is chromocenter. A chromocenter is an area in which centric, heterochromatic segments of one or more chromosomes form a compact arrangement. Hence, this is also the incorrect option

Solution
The centromere is the region of a chromosome where sister chromatids are joined during cell division. Spindle fibers bind to the centromere through the kinetochore during mitosis. Centromeres were initially identified as genetic loci that guide chromosome behavior. As a result, C is the right answer.

Note
1) A chromosome is said to be acentric if it lacks a centromere.
2) Ciliates, for example, have hundreds of acentric chromosomes in their macronucleus.
3) Acentric chromosomes or acentric fragments may also result from chromosome-breaking events.