Final answer:
Aneuploid and haploid cannot happen in 3) animals due to meiosis restrictions, but they can occur in plants which frequently display polyploidy. Hence, 3) is correct.
Step-by-step explanation:
An individual with more than the correct number of chromosome sets (two for diploid species) is called polyploid. Polyploid animals are extremely rare and mostly sterile, with only a few examples among certain groups of animals like flatworms, crustaceans, amphibians, fish, and lizards. However, aneuploid and haploid cannot happen in animals because meiosis cannot proceed normally with an odd number of chromosome sets.
In contrast, polyploidy is very common in the plant kingdom, where polyploid plants tend to be larger and more robust than their euploid counterparts.