In a punnets square for a two-factor cross is it possible for all the offsprings to be identical? Explain why or why not

The Punnett board or chart is a diagram designed by Reginald Punnett and is used by biologists to determine the probability that a product has a particular genotype. The Punnett square allows us to observe each possible combination to express, the dominant alleles (represented by uppercase letters) and recessive (lowercase letters), shows us all possible types of descendants that could occur at the intersection. The probability that the product has the BB genotype is 25%, with Bb it is 50% and with bb 25%. All genotypes are alleles, therefore all are known as a normal or adjacent punnett.

It would have to be BB x BB or BB x bb