In Birds,a Gene Encoding a Ca²⁺-Activated K⁺ Channel Is Expressed

Multiple Choice

In birds,a gene encoding a Ca²⁺-activated K⁺ channel is expressed in auditory hair cells as multiple mRNAs,which encode for proteins that open at different Ca²⁺ concentrations.The Ca²⁺ concentration at which the channel opens allows these cells to respond to different sound frequencies.Which one of the following would explain the appearance of the various isoforms of this particular channel?

A) the presence of chain-terminating mutations
B) exon skipping
C) the absence of compensating mutations
D) alternative splicing