Step 1: Understanding the Concept
Single cell protein (SCP) is dried microbial biomass used as food or feed.
Step 2: Statement I
SCP is obtained from bacteria, yeasts, fungi and algae such as Spirulina, not from bacteria alone. So the statement is incorrect.
Step 3: Statement II
The fruiting bodies of mushrooms and truffles have almost no sugar or fat but are rich in proteins, vitamins, minerals and amino acids. So the statement is correct.
Step 4: Select the option
Statement I is incorrect and statement II is correct.
Final Answer:
Statement I is incorrect but statement II is correct.
\[ \boxed{\text{(D) }\text{Statement - I is incorrect but statement - II is correct.}} \]