You want to find out which of the consequent gene X or Y is being transcribed. For this you do a hybridization competition analysis and plot the radioactivity curve with increasing concentration of the competitor unlabelled mRNA. If the transcribed gene was X, which observation fits your result?

• A. The radioactivity of y decreases while that of x remains the same
• B. The radioactivity of x decreases while that of y remains the same
• C. The radioactivity of x and y decreases
• D. The radioactivity of y decreases while x increases