Bats have a problem: how to find their Way around in the dark. They
hunt at night, and therefore (1)(ア cannot イ find ウ help エ light
オ them 力 to キ use) food and avoid obstacles. You might say that
下 is a problem it is one of their own making, which they could avoid Simply
by changing their habits and hunting by day. However, other creatures such
as birds already take advantage of the daytime economy. Given that there is
a jiving to be made at night, and given that alternative daytime trades are