In commercial Cheddar and hard cheese manufacture, standardization of cheese milk requires adjusting the casein-to-fat (C/F) ratio to between 0.68 and 0.70 (commonly 0.70). This optimal ratio guarantees that the resulting ripened cheese achieves the legal regulatory minimum of $50\%$ fat in dry matter (FDM) while maximizing curd yield and desired texture.

Sherry is a famous fortified wine originating from Jerez in southwestern Spain (Andalusia). Unique styles of sherry (or sherry-type baking processes) involve maturing the fortified wine in oak casks stored in warm, sun-exposed bodegas or warm chambers at elevated temperatures ($40-55^\circ\text{C}$) for 3 to 6 months to develop distinctive oxidized, nutty, and caramelized flavor bouquets.

Sulfites/bisulfites (potassium metabisulfite, $\text{K}_2\text{S}_2\text{O}_5$, generating free $\text{SO}_2$) are the primary, indispensable chemical preservative in winemaking, inhibiting wild yeasts, acetic acid bacteria, and preventing oxidative browning. Diethyl pyrocarbonate (DEPC / baycovin) was historically widely utilized in enology as a cold sterilant/preservative against yeast fermentation in bottled wines. Citric acid is an acidulant, not a primary antimicrobial preservative. Thus, (A) and (C) only is the designated official answer.

Food industry operational terms:

• Bloom (fat bloom or sugar bloom) refers to the whitish, greyish discoloration on chocolate caused by cocoa butter polymorphic transformation or sugar recrystallization.
• Overrun refers to the percentage volume increase in ice cream caused by the incorporation of air during freezing.
• Crumb refers to the soft, porous interior structure of baked bread surrounded by the crust.