One Positive Effect of the Last Ice Age Was That

One positive effect of the last ice age was that it allowed for settlement of many parts of the earth not normally in reach of humans.What effect led to this accelerated settlement?

A) much higher sea levels that allowed for shallower coastal zones and thus easier boat landings
B) much lower sea levels that resulted in many areas being connected together by land bridges
C) faster current speeds on the oceans of the world which resulted in faster,safer,boat trips
D) less volcanism due to thick ice caps thus making travel safer in the mid-to low latitudes