Answer:
A. Hundred millions.
Explanation:
Growing up, the easiest method I've found in terms of finding which place a number is is as follows: change the number you're looking for into a 1, change everything after it into a 0, drop everything before it, and ask yourself what that number is. That may seem a little odd, but here's some examples.
Let's say we have the number 91,582. We want to figure out what place the 5 is in. First, let's change the 5 into a 1, like so: 91,182. Next, we'll change all the numbers afterwards into 0s, like so: 91,100. Finally, we'll drop every number before the 1, leaving us with 100. Now, ask yourself what that number is. It's one hundred. That means that the 5 is in the one hundreds place.
Let's apply this to our given number. First, let's go ahead and change our 6 into a 1: 7,114,118,872. Next, let's change all the numbers after the 1 into 0s: 7,100,000,000. Finally, let's drop all numbers before our 1: 100,000,000. Our final number is one hundred million. This means that the 6 is in the one hundred millions place. Please let me know if you have any questions!