As of June 2018, how many confirmed exoplanets had been discovered by the Kepler program?

The correct answer is based on the achievements of the Kepler Space Telescope, which was launched to discover Earth-sized planets orbiting other stars. By June 2018, a total of 2,327 confirmed exoplanets had been cataloged as a result of Kepler's data. The significance of this number lies in its illustration of the telescope's success in expanding our understanding of planetary systems beyond our own, as it provided vital insights into the diversity of planetary sizes and orbital distances.

The figure of 2,327 reflects the culmination of years of meticulous observations and data analysis, demonstrating Kepler's capability to identify planets that could potentially support life. This milestone in exoplanet research has helped to shape our understanding of the universe’s structure and the potential for discovering life on other planets.