Answer:
Bacteria
Step-by-step explanation:
Bacteria constitutes large group of unicellular organisms that lacks membrane bound organelles and constitute cell wall. Bacteria are used for the production of recombinant proteins.
Bacteria can be selected easily for the recombinant protein formation. The plasmid of bacteria is helpful for the integration of desired genes and the production of protein. The bacteria culture can be maintained easily in the laboratory. The different strains of bacteria with different traits can be used for the production of different recombinant proteins at low cost.
Thus, the correct answer is option (1).