Answer:
C-mutiple strands exchange are common.
Step-by-step explanation:
The relative measure of distance between two linked genes is known as A MAP UNIT.it is also the distance between a gene and centromere,
The higher the fequemcies or the number of crossover (fexchanged of genetic mateials at meiosis i&iii,) the larger the MAP distances measured between genes.
Therefore the less accuracy is due to higher frequency of crossing over which increases the MAP distances making MAP units determination less accurate to measure ;since the distance from mutiple crossovers has double
The number of map unit is obtained by dividing the percentage of crossover by 2.
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