Final answer:
The central element of the synaptonemal complex is made up of zip proteins (A). These proteins, along with cohesin proteins at the centromere, help in the proper alignment and holding together of homologous chromosomes during prophase I of meiosis.
Step-by-step explanation:
The central element of the synaptonemal complex during meiosis is composed of proteins known as zip proteins. These proteins help to hold the homologous chromosomes together in preparation for crossing over. During prophase I of meiosis, homologous chromosomes come together to form a synapse. They are bound tightly in alignment by the synaptonemal complex and by cohesin proteins at the centromere.
The process of crossing over, or recombination, is facilitated by the synaptonemal complex, but spindle microtubules are not responsible for the transfer of DNA during crossover as they are involved in the movement of chromosomes during cell division. Sister chromatids are separated from each other during anaphase II of meiosis. The cohesion of identical copies of chromatin is maintained by cohesin at the centromere. These identical copies are known as sister chromatids. Lastly, the ends of linear chromosomes are maintained by telomerase.
So, the answer is A.