Bacteria can replicate once:
A. Every 20 seconds
B. Bacteria can not replicate without the help of a host
C. An hour
D. Every 24 hours

most bacteria replicate every 20 minutes, if the conditions are good. i really dont know about the other answers, because bacteria can live outside of a host, longer than a normal virus can. and for sure its NOT A or C. so its a 50-50 shot B or D. sorry i couldn't help any further

Explanation:

they each offer a fresh glut of resources to the organisms that can arrive and exploit them. as individuals and new species continue to appear, they actively and passively alter the environment. competition for shared resources increases, local abiotic and biotic conditions shift, and the relative abundances of species change accordingly. the process is called ecological succession, and it is one of the earliest and most well-known concepts in ecology.

i think that d. wind is the answer.   i missed the question when i answered a. currents.