I guess the question itself is written in a wrong way, i guess
that the question means Murabaha not murahba since there is nothing
called "murahba LC", but there is "Murabaha LC" or to be adequate
"LC Murabaha"
This is a sharia compliant product used in importing goods
through islamic banks or financing companies.
It is differ from Cash LC that the later requires the LC amount
to be ready with the importer while the other option Murabaha will
be financed by the Bank