A Computer Program Recognizes an ORF by Looking for Ribosomal

A computer program recognizes an ORF by looking for ribosomal binding sites, start codons, and stop codons with an appropriate number of nucleotides between each element. What is a drawback of this approach?

A) Too many ORFS are identified, most of which are stretches on non-coding junk DNA.
B) Codon bias causes incorrect annotations.
C) Legitimate genes and non-coding RNA may be missed.
D) We lack the computing power to complete the analyses in a timely manner, thus many genomes are only partially annotated.