Revenue generated by companies A and B in the year 2016: 225+245= 470

Revenue generated by companies B and C in the year 2018: 280+310 = 590

We are asked that first number is what percentage of the second number; this can be calculated by $$\frac{47}{59}\times\ 100$$

Here, the denominator is very close to 60. Approximating the value of the denominator to 60, we get the percentage value to be 78.33%

Since we have approximated up the value of the denominator, the  percentage value would be a little higher than 78.33%

Of the given options, 79.66% is the only number that would satisfy our requirements. 

Therefore, Option C is the correct answer.