Answer: b. 50%
Explanation:
When a heterozygous brown-eyed rabbit (Bb) is crossed with a homozygous dominant brown-eyed rabbit (BB), we can use the Punnett square to predict the offspring's genotypes.
The Punnett square for this cross would look like this:
B | b
----------------
B | BB | Bb
----------------
B | BB | Bb
----------------
From the Punnett square, we can see that 50% of the offspring are predicted to be homozygous dominant (BB), so the correct answer is:
a. 50%
Hope this helps!