Question

test tube below were allowed to stand at room temperature for 12 hours, what process would be occurring in the test tube image: test tube with airtight stopper, yeast + glucose solution protein synthesis aerobic respiration fermentation photosynthesis

Explanation:

The test tube is airtight (no oxygen), with yeast and glucose. Yeast performs fermentation (anaerobic respiration) in absence of oxygen to produce energy, converting glucose. Protein synthesis, aerobic respiration (needs O₂), and photosynthesis (by plants/algae, not yeast) don't fit. So fermentation is the process.

Answer:

fermentation