C. testable and observable
I think it is B I had done these.
The leaves!
They have chlorophyll to take energy from the sun and use it.
Answer: Option B - There are more than four genes that determine this trait.
Explanation:
The tobacco plant species have its leaf colour with characteristics that changes gradually over a range of values, which refers to continuous variation.
Note that continuous variation keep expressing gene variants in successive generations of the tobacco plants, that differs from the parents. So, there are MORE THAN four genes controling the expression of varying phenotypes in the leaves
