Read the passage below:
When horologist Mateo Silva patented his revolutionary dual-balance escapement mechanism in 1928, scholars assumed it was the culmination of his Madrid period. However, Silva had actually sketched the preliminary designs for the escapement four years prior, while convalescing from fever in Toledo. Before establishing his Madrid laboratory in 1924, he completed a rigorous three-year apprenticeship under master clockmaker Alonzo Perez, during which he restored the municipal tower clock. Immediately following his move to Madrid, Silva initiated a series of systematic friction experiments on brass gears. These experiments formed the core of a treatise he published in 1926, two years before obtaining his patent and five years prior to securing commercial manufacturing backing in 1931.
According to the passage, which of the following events occurred FIRST chronologically?
- ASketching the preliminary designs for the dual-balance escapement
- Completing an apprenticeship under master clockmaker Alonzo PerezCevap
- CInitiating a series of systematic friction experiments on brass gears
- DPublishing a treatise on friction reduction in brass gears