Egyptians are credited as having pioneered preserving methods as long ago as 2650 B.C.Some bat caves, like honey-bee hives, have residents that take on different duties such as defending the entrance, acting as guards and to sound a warning at the approach of danger, and scouting outside the cave for new food and roosting sites.
as having
with having
to have
as the ones who
Explanation:
Correct Answer is: with having acting as guards and sounding
