How Were Researchers Able to Produce Silk from Algae

How were researchers able to produce silk from algae?

A) by feeding algae the components needed to produce silk as waste
B) by inserting the silk gene into the DNA of algae for expression
C) by extracting the same silk compound from the algae cell wall
D) by using enzymes from algae to synthesize the silk protein
E) by removing the gene that inhibits silk synthesis is algae