Which statement best supports the land bridge theory of early migration?

Land Bridge theory is the theory that explains the migrations of humans to America. According to this theory, the ancestors of Native inhabitants crossed the Bering bridge Which emerged between Alaska and Siberia between 40,000 and  15,000 years ago. Archaeological evidence put the date of human existence in the Americas to be 13,000 years ago. The bridge emerged during the last ice age. According to the theory that challenges the Beringia theory that Beringia was flooded and the inhabitants had to migrate to Alaska and also that they ferried themselves in boats. Another theory states that the entry to North America was blocked by two ice sheets Laurentide and Cordilleran. The hunter-gatherers lived on the Beringia landmass hunting Mammoth and Reindeer and later when the climate became warmer they continued their journey. This happened in a cyclic manner

2018 means 2018 ce or common era

there have been other eras too including bce, which included way more years.