Identify the incorrect statement regarding a sex limited trait:
1. This term refers to a trait controlled by a gene located on the X or Y chromosomes.
2. This is a trait that occurs more frequently in one sex than another.
3. This is an extreme example of a sex influenced trait.
4. This trait is likely to be a secondary sex characteristic.

All the following statements regarding lethal allele are true except
1. Lethal alleles are always recessive.
2. Lethal alleles may have a late age of onset.
3. Lethal alleles may be caused by mutations in essential genes.
4. Lethal alleles may affect one individual differently than another.

In heterozygous condition, the dominant allele is able to express itself only in one sex. This is a
1. A sex limited trait
2. A sex influenced trait
3. A sex linked trait
4. sex-determining trait.