The laser type that provides very narrow spectral widths, (<10ukHz) in the 1550nm range for DWDM applications (as shown in the graph), is an example of a:

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The graph represents optical signal power versus wavelength measurement from 1550nm to
1560nm. The laser type that provides very narrow spectral widths, (<10ukHz) in the 1550nm range
for DWDM applications (as shown in the graph), is an example of a:

A.
Red Light Emitting Diode laser

B.
Fabry-Perotlaser

C.
Distributed Feedback laser

D.
Edge Emitting LED laser

E.
Vertical Cavity Surface Laser