Answer:
Option D, TT ´ tt
Step-by-step explanation:
Allele for tallnes "T" is dominant over the recessive allele "t"
The genotype of a heterozygous tall offspring will be "Tt"
When a cross is carried out between "TT " and "tt" , the following offspring are produced -
T T
t Tt Tt
t Tt Tt
All the offspring have genotype "Tt" which is a heterogyzous allele pair.
Since "T" is dominant over "t", all the alleles would be heterozygous tall.
Thus, in order to produce 100 percent heterozygous tall offspring, the cross must be carried out between "TT" and "tt".
Option D is correct