If someone who is homozygous for an autosomal recessive disorder mates with a person who does
not carry the mutated gene their child will
have a 100 percent chance of developing the disease
have a 25 percent chance of developing the disease
have a zero percent chance of developing the disease
have a 50 percent chance of developing the disease

have a zero percent chance of developing the disease

Explanation: example aa for disorder mates with AA (doesn't have the mutation), all offspring will be Aa.  Offspring will be a carrier of the autosomal recessive disorder but will not develop the disease

if your own plato the answer is b. the fern transitioned from sporophyte generation to gametophyte generation.