What year was the California Seed Act approved to regulate the seed market?

The California Seed Act was approved in 1921 to create a regulatory framework for the seed market. This legislation was crucial in establishing measures to ensure the quality and labeling of seeds sold within the state. The Act aims to protect both consumers and producers by providing guidelines on seed quality, purity, and germination standards, ensuring that sellers accurately represent their products. This historical context highlights the importance of the 1921 date in the development of seed regulation, making it the correct answer to the question.