The correct answer is:
Yes, because the trees in the sample are chosen randomly. The sample size also appears to be large enough to avoid bias.
A random sample helps to ensure that the selection is representative of the larger population, and 700 is typically considered a sufficient sample size for making generalizations, assuming the sample is representative. The fact that all trees in the sample have at least 230 apples suggests a minimum quality, but the randomness of the pick and the size of the sample are the most critical factors for the validity of her generalization.