One of the reasons bacteria can be so deadly is because they multiply very quickly. E. coli has a doubling time of around 15 minutes. This means that if 100 bacteria are left alone for 2 hours, they will multiply to become:

12,400 Bacteria

18,400 Bacteria

25,600 Bacteria

36,600 Bacteria

The correct answer is - 25600 bacteria.

Explanation:

Bacteria can divide and produce double their population very quickly. As mentioned in the question bacteria multiply every 15 minutes to their double number. Finding the number of bacteria after 2 hours is simple mathematics. Two hours means 120 minutes and dividing it to 15. The result will be 8 which mean the bacteria double their colony 8 time so,

100*2 to the power 8 = 100 (initial number of bacteria) * 2*2*2*2*2*2*2*2 = 25600

Thus, the correct answer is option - 25600 bacteria.