A farmer grows crops with an average height of 5 feet. He breeds his tallest plants, which are each 8 feet tall. They produce offspring that have an average height of 5.25 feet.

So, the heritability in this case is qa. The trait for height is. qb

Qa: 1: 0.08 / 2: 0.1 / 3: 0.5 / 4:0.8/

Qb: 1 completly influenced by environment

2 completely influenced by genes

3 slightly influenced by environment

4 slightly influenced by genes.

Qa: The heritability for tallness in these crops is 0.08, while Qb: Genes slightly influence the trait for height.

Step-by-step explanation:

Qa: The average height of regular crops grown by the farmer was 5 feet. The amazingly tall breeds have a 3feet increment than the usual crops. This progeny of the farmer's choice breeds has a 0.25 feet increment in height than what is expected in other normal breeds. Therefore, the heritability of the tall trait by these progeny was 0.25/3, which is 0.08333 ... Approximately 0.08.

Qb: This low heritability index showed that the trait for tallness is slightly influenced by gene, because if otherwise, the index would have been a far way higher than this. However, we cannot conclude that it is the environment that determines the tall phenotype to be expected in the crops; this renders other options wrong.