Shared mechanism of protein synthesis

Steps:

• Identify key cellular processes universal to life: both eukaryotes and bacteria use DNA as genetic material and synthesize proteins via translation.
• Eliminate D: eukaryotes have linear chromosomes, while bacteria have circular DNA.
• Assess A: respiration occurs in both, but not all bacteria respire (many are anaerobic).
• Confirm C: in both, mRNA binds ribosomes for translation, following the central dogma.

Why C is correct:

• The central dogma of molecular biology requires mRNA to bind ribosomes in all cells for protein synthesis from genetic code.

Why the others are wrong:

• A. Many bacteria are obligate anaerobes that ferment instead of respire.
• B. DNA containment is universal to all cells, not a distinguishing shared feature.
• D. Eukaryotes contain linear DNA in the nucleus, not circular.

Final answer: C