Correct option is A
Explanation-
Autopolyploidy occurs when an organism has more than two complete sets of chromosomes, and all of these sets are derived from a single species. This typically happens via genome duplication within the same species, not involving hybridization.
So, if a diploid species (2n) becomes tetraploid (4n) due to nondisjunction or chromosome duplication, and all chromosomes come from that same species, it is autopolyploidy.
So, the correct answer is option a - More than two sets of chromosomes, both of which are from the same parental species. The wording “both of which” might sound like only two sets, but it actually refers to each set in a polyploid condition being from the same species.
Incorrect options-
Option b : More than two sets of chromosomes, both of which are from different parental species.
This describes allopolyploidy, not autopolyploidy.
Option c: More than two sets of chromosomes only from a single parent.
Although it seems similar to autopolyploidy, it uses "single parent" instead of "single species", which is vague and potentially misleading. This could be interpreted as parthenogenesis or asexual reproduction, not necessarily involving chromosomal duplication.
Option d : Duplication of a chromosomal locus leading to spontaneous increase in the copy number of a gene.
This refers to gene duplication, not whole-genome duplication. Autopolyploidy involves duplication of the entire set of chromosomes, not just a single locus or gene.
