Question

crossing a bb parent with a bb parent results in
a b or b offspring.
b bb, bb and bb offspring.
c half bb and half bb offspring.
d all bb offspring.

Explanation:

Step1: Determine gametes of parents

The BB parent can only produce B gametes. The bb parent can only produce b gametes.

Step2: Use Punnett square

When we cross B (from BB parent) and b (from bb parent), all offspring will have the genotype Bb.

Answer:

d. all Bb offspring.