Test analysis: value determines price. The socially necessary labor time determines the value of goods. Therefore, the price of gold is determined by the socially necessary labor time for producing gold. Therefore, item A is selected in this question, and item BCD does not meet the meaning of the question, so it is excluded.
Comments: The key to answering this question correctly is to find out that socially necessary labor time determines the value of goods, and then analyze and eliminate them one by one. This question is moderately difficult. Remember, influencing factors and determining factors are different.