Answer: C. 180 times
Explanation:
From the 60 trials, the percentage of times Laura picked a green marble was:
= 100% - Percentage of times blue and red were picked
= 100% - 25% - 15%
= 60%
If these results were repeated with 300 trials, the number of times Laura would be expected to pick green would be:
= 60% * 300
= 180 times