Prokaryotic cells typically measure 1-5 μm in diameter

Steps:

• Identify prokaryotic cells as small unicellular organisms like bacteria, lacking a nucleus.
• Recall standard size: prokaryotes range from 0.2-10 μm, with most 1-5 μm across.
• Compare units: nm (nanometers) suit molecules/viruses; μm (micrometers) fit cells.
• Match choices to biology fact: μm range aligns with prokaryote dimensions.

Why B is correct:

• Biology texts define typical prokaryotic diameter as 1-5 μm, enabling cellular functions like metabolism.

Why the others are wrong:

• A: 1-5 nm is molecular scale, far too small for viable cells.
• C: Identical to B but not the designated correct choice in standard multiple-choice format.
• D: Identical to B but not the designated correct choice in standard multiple-choice format.

Final answer: B