Correct choice is (a) True
For explanation I would say: It combines hexamer frequencies with coding signals (initiation codons, TATA box, cap site, poly-A, etc.) in prediction. Putative exons are assigned a probability score (P) of being a true exon. Only predictions with P > 0.5 are deemed reliable. This program is trained for sequences from vertebrates, Arabidopsis, and maize. It has been used extensively in annotating the human genome.