Generally seedless watermelon is

Answer: Option B

Generally, seedless watermelon is Triploid. They have three sets of chromosomes. This odd number results in them being sterile and not producing seeds. The way they become triploid is by mating a diploid male with a tetraploid female.
The ordinary seeded watermelons are Diploid melons, meaning, that a typical watermelon has 22 chromosomes (diploid) while a seedless watermelon has 33 chromosomes (triploid).