Directional selection Reverse transcription Directional sele

Directional selection

Reverse transcription Directional selection Purifying selection Transcription The introduction of new mutations

Selected RNA population 1. RNA population DNA template cDNA

Solution

In the above cycle indicates the process of reverse transcription. Some organisms are utilizing the RNA as a template to generate cDNA and then new DNA template. This phenomenon is also known as reverse transcription and commonly observed in virus (retrovirus).

In the above cycle, cDNA is generated from RNA which taking in the step 3 of the cycle. The step 2 in the above cycle is conducting a selection (directional section) of these RNAs from the total cellular pool.

Hence, the correct answer is Directional selection