Ans. The correct answer is to complete the sentence is 'reproduce more rapidly.'
In order to adapt into new environmental conditions, organisms need to change their genetic makeup that help them to survive in changed conditions.
Bacteria are microscopic organisms, which reproduce more quickly than larger, complex organisms. So, they undergo rapid changes or mutations, which help them to survive more easily in changed environment.
On the other hand, elephants are complex, multicellular organisms, in which reproduction is slow. Due to this, elephants need more time than bacteria to adapt changed conditions.
Hence, bacteria can easily adapt to changing environments as compared to elephants.