Identify the region 'X', the factor 'Y' and the enzyme 'Z' involved in the process of transcription in prokaryote as shown in the schematic representation given below.

Correct Option:
Region 'X' - Promoter
Factor 'Y' - Sigma (σ)
Enzyme 'Z' - RNA polymerase

Explanation:
The schematic representation depicts the initiation step of transcription in a prokaryote. By analyzing the visual labels and components in the provided diagram, we can determine the identities of 'X', 'Y', and 'Z':

1. Region 'X' (Promoter):
The label 'X' points to the region of the DNA double helix where the DNA strands begin to unwind (forming the transcription bubble). This regulatory sequence of DNA, located upstream of the structural gene, is the Promoter. It determines where transcription starts and which DNA strand is read as the template.

2. Factor 'Y' (Sigma factor):
The label 'Y' points to the regulatory protein subunit nestled within the main enzyme complex. In prokaryotes, this is the
$\sigma$ (sigma) factor
which is required for the initiation of transcription. It specifically recognizes and binds to the promoter sequence, positioning the RNA polymerase enzyme at the correct start site. Once elongation begins, the sigma factor dissociates.

3. Enzyme 'Z' (RNA polymerase):
The label 'Z' points to the entire oval-shaped protein structure carrying out transcription. This is RNA polymerase, the primary enzyme responsible for synthesizing RNA from a DNA template. In prokaryotes, a single type of RNA polymerase catalyzes the transcription of all types of RNA (mRNA, tRNA, and rRNA).

Therefore, Region 'X' is the Promoter, Factor 'Y' is the Sigma (σ) factor, and Enzyme 'Z' is RNA polymerase.