It was once assumed that a count of the number of protein-coding genes in an organism would provide a reasonable estimate of the total number of gene products. this is now known to be incorrect, largely due to the discovery of widespread:

a.
translational control

b.
transcriptional initiation control

c.
alternative splicing

d.
chromatin modification control

The correct answer is option c, that is, alternative splicing.

Explanation:

When a solitary pre-mRNA molecule is processed in two or more than two ways to produce two or more RNA it is known as alternative splicing. This distinct RNA post-translation produces different products of genes. It takes place when one 5 prime splice site of the intron is associated with more than one 3 prime splice sites and is possibly mediated by the structural conformation of RNA and some of the splicing regulators, like SR protein.  

The alternative splicing takes place distinctly in different cell types and is also monitored by the cell type-specific factor. The remaining of the options are not correct as these options are related to the process control mechanism.  

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