Final answer:
Euploidy is the condition of having the normal chromosome count for a species. In humans, euploidy is 22 pairs of autosomes and one pair of sex chromosomes. Therefore, the correct answer is b. Normal chromosome count.
Step-by-step explanation:
Euploidy refers to the condition where an individual has the normal chromosome count appropriate for their species. In humans, this means having 22 pairs of autosomes and one pair of sex chromosomes, which makes option b. Normal chromosome count the correct answer. Aneuploidy contrasts with euploidy and represents a deviation from the normal number, such as in cases of monosomy or trisomy where there are missing or extra chromosomes, respectively. It's important to note that situations like the well-known Down Syndrome, which is caused by trisomy 21, underscore the significance of gene dosage and the adverse effects that can arise from aneuploidy.