• Flour Specifications for High-Ratio Cakes:
• Enzymatic Activity:
• Cake flour requires low $\alpha$-amylase activity (indicated by high Falling Number $\gt 300 - 400\text{ s}$).
• Excess $\alpha$-amylase degrades gelatinized wheat starch into maltodextrins during oven baking, weakening the gas-cell structure and causing cake collapse and a sticky, wet crumb.
• Conclusion: Low a-amylase activity (Option 1).

Correct option: (1) Low a-amylase activity